Alert archive / Colorado / Red Flag Warnings in 2020
Red Flag Warning 24, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this red flag warning at Sep 4, 2020, 2:40 PM MDT for 18 counties in Colorado. It took effect at Sep 6, 2020, 12:00 AM MDT. It was in force for 44 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 4, 2020, 2:40 PM MDT (20:40 UTC)
- In effect from
- Sep 6, 2020, 12:00 AM MDT
- Expired
- Sep 7, 2020, 7:54 PM MDT
- In force
- 44 hr
- Issued by
- NWS Denver/Boulder, CO
Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Clear Creek County, CO, Elbert County, CO, Gilpin County, CO, Grand County, CO, Jackson County, CO, Larimer County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Park County, CO, Phillips County, CO, Sedgwick County, CO, Summit County, CO, Washington County, CO, Weld County, CO
The radar
The Denver radar (KFTG), 28 km from the middle of the area, began a volume at 20:39 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 8.7 hours before the alert went out and 114 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2997 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 9 m²/s²
- 0-3 km storm-relative helicity
- 28 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
091 WWUS85 KBOU 042040 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 240 PM MDT Fri Sep 4 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado Sunday and Monday. The high fire danger may spread to the northern foothills and across the plains on Sunday as well. COZ211>213-217-218-051200- /O.NEW.KBOU.FW.W.0024.200906T1800Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 240 PM MDT Fri Sep 4 2020 ...RED FLAG WARNING IN EFFECT FROM NOON SUNDAY TO 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... The National Weather Service in Denver has issued a Red Flag Warning FOR WIND AND LOW RELATIVE HUMIDITY, which is in effect from noon Sunday to 8 PM MDT Monday. * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Sunday noon through early evening Monday. * Relative Humidity...As low as 9 percent during the afternoon hours, recovering only to around 30 percent Sunday night. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ215-238-242>251-051200- /O.NEW.KBOU.FW.A.0016.200906T1600Z-200907T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 240 PM MDT Fri Sep 4 2020 ...FIRE WEATHER WATCH IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MOST OF THE NORTHEAST PLAINS OF COLORADO... The National Weather Service in Denver has issued a Fire Weather Watch FOR WIND AND LOW RELATIVE HUMIDITY, which is in effect from Sunday morning through Sunday evening. * Affected Area...Fire Weather Zones 215...238...242...243... 244...245...246...247...248...249...250 and 251. * Winds...Northwest 15 to 20 mph with gusts up to 30 mph. * Timing...Late Sunday morning until early Sunday evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings. && $$
10 follow-up statements
047 WWUS85 KBOU 050917 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 317 AM MDT Sat Sep 5 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado Sunday and Monday. The high fire danger may spread to the northern foothills and across the plains on Sunday as well. COZ215-238-242>251-052100- /O.UPG.KBOU.FW.A.0016.200906T1600Z-200907T0200Z/ /O.EXB.KBOU.FW.W.0024.200906T1800Z-200907T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 317 AM MDT Sat Sep 5 2020 ...RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... The National Weather Service in Denver has issued a Red Flag Warning FOR WIND AND LOW RELATIVE HUMIDITY, which is in effect from noon to 8 PM MDT Sunday. The Fire Weather Watch is no longer in effect. * Affected Area...Fire Weather Zones 215...238...242...243... 244...245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Late Sunday morning until early Sunday evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-217-218-052100- /O.CON.KBOU.FW.W.0024.200906T1800Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 317 AM MDT Sat Sep 5 2020 ...RED FLAG WARNING REMAINS IN EFFECT FROM NOON SUNDAY TO 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Sunday noon through early evening Monday. * Relative Humidity...As low as 8 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
954 WWUS85 KBOU 051817 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 1217 PM MDT Sat Sep 5 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado Sunday and Monday. The high fire danger may spread to the northern foothills and across the plains on Sunday as well. COZ215-238-242>251-060230- /O.EXT.KBOU.FW.W.0024.200906T1600Z-200907T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1217 PM MDT Sat Sep 5 2020 ...RED FLAG WARNING NOW IN EFFECT FROM 10 AM TO 8 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zones 215...238...242...243... 244...245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Late Sunday morning until early Sunday evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-217-218-060230- /O.EXT.KBOU.FW.W.0024.200906T1600Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 1217 PM MDT Sat Sep 5 2020 ...RED FLAG WARNING NOW IN EFFECT FROM 10 AM SUNDAY TO 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Sunday noon through early evening Monday. * Relative Humidity...As low as 8 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
215 WWUS85 KBOU 060226 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 826 PM MDT Sat Sep 5 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado Sunday and Monday. Downslope winds will increase the fire danger in the northern Front Range foothills later tonight, then spread across the plains on Sunday. Humidities are expected to be a little higher at lower elevations on Monday, but conditions could still be near Red Flag criteria. COZ215-061200- /O.EXT.KBOU.FW.W.0024.200906T0600Z-200907T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- 826 PM MDT Sat Sep 5 2020 ...RED FLAG WARNING NOW IN EFFECT FROM MIDNIGHT TONIGHT TO 8 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zone 215. * Winds...Northwest 10 to 20 mph with gusts up to 35 mph. * Timing...Midnight Saturday night until early Sunday evening. * Relative Humidity...As low as 9 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ238-242>251-061200- /O.CON.KBOU.FW.W.0024.200906T1600Z-200907T0200Z/ Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 826 PM MDT Sat Sep 5 2020 ...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM TO 8 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zones 238...242...243...244... 245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Late Sunday morning until early Sunday evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-217-218-061200- /O.CON.KBOU.FW.W.0024.200906T1600Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 826 PM MDT Sat Sep 5 2020 ...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM SUNDAY TO 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Sunday noon through early evening Monday. * Relative Humidity...As low as 9 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ Gimmestad
608 WWUS85 KBOU 061324 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 724 AM MDT Sun Sep 6 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado today and Monday. Downslope winds will increase the fire danger in the northern Front Range foothills and plains today. Humidities are expected to be a little higher at lower elevations on Monday, but conditions could still be near Red Flag criteria. COZ215-062130- /O.CON.KBOU.FW.W.0024.000000T0000Z-200907T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- 724 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zone 215. * Winds...Northwest 10 to 20 mph with gusts up to 35 mph. * Timing...Today into early this evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ238-242>251-062130- /O.CON.KBOU.FW.W.0024.200906T1600Z-200907T0200Z/ Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 724 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zones 238...242...243...244... 245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Late this morning until early this evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-217-218-062130- /O.CON.KBOU.FW.W.0024.200906T1600Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 724 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Noon today through early this evening. * Relative Humidity...As low as 10 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
115 WWUS85 KBOU 061752 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 1152 AM MDT Sun Sep 6 2020 ...EXTENDED PERIOD OF HIGH FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado today and Monday. Downslope winds will increase the fire danger in the northern Front Range foothills and plains today. Humidities are expected to be a little higher at lower elevations on Monday, but conditions could still be near Red Flag criteria. COZ215-070200- /O.EXT.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Larimer and Boulder Counties Between 6000 and 9000 Feet- 1152 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING NOW IN EFFECT UNTIL 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zone 215. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Today into early this evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ238-242>251-070200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200907T0200Z/ Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1152 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE NORTHERN FRONT RANGE FOOTHILLS AND MUCH OF THE NORTHEAST PLAINS, FIRE WEATHER ZONES 215, 238, AND 242 THROUGH 251... * Affected Area...Fire Weather Zones 238...242...243...244... 245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Late this morning until early this evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-217-218-070200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 1152 AM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS AND HIGH MOUNTAIN VALLEYS... * Affected Area...Fire Weather Zones 211...212...213...217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Noon today through early this evening. * Relative Humidity...As low as 10 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
556 WWUS85 KBOU 062132 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 332 PM MDT Sun Sep 6 2020 ...EXTENDED PERIOD OF EXTREME FIRE DANGER... .Record or near record heat, very dry conditions, and increasing winds will bring critical fire danger to much of the northern mountains and high valleys of northern Colorado through Monday. Downslope winds will increase the fire danger in the northern Front Range foothills as well. Poor humidity recovery will occur overnight, and Monday will see another day of dry and breezy conditions with extreme fire danger. Conditions on the plains will improve this evening as winds decrease. COZ238-242>251-070200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200907T0200Z/ Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 332 PM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR MUCH OF THE NORTHEAST PLAINS OF COLORADO... * Affected Area...Fire Weather Zones 238...242...243...244... 245...246...247...248...249...250 and 251. * Winds...North 10 to 20 mph with gusts up to 30 mph. * Timing...Until 8 pm this evening. * Relative Humidity...As low as 8 percent. * Impacts...Rapid fire growth will be possible. Avoid any activity outdoors that may produce a spark. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ COZ211>213-215-217-218-070600- /O.CON.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- Larimer and Boulder Counties Between 6000 and 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 332 PM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS...HIGH MOUNTAIN VALLEYS...AND NORTHERN FRONT RANGE FOOTHILLS... * Affected Area...Fire Weather Zones 211...212...213...215... 217 and 218. * Winds...West 15 to 20 mph with gusts up to 35 mph. * Timing...through tonight and Monday. * Relative Humidity...As low as 9 percent during the day, and humidity recovery only to around 30 percent tonight. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
035 WWUS85 KBOU 070213 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 813 PM MDT Sun Sep 6 2020 ...ONE MORE DAY OF EXTREME FIRE DANGER IN THE MOUNTAINS... .Temperatures will remain mild with low humidities over the mountain ridges and foothills overnight, though winds will be lighter. Monday will bring one more day of near record heat and very low humidities, and stronger winds. Conditions on the plains have improved as humidities increased and winds diminished this evening. However, it will be hot and breezy on the plains again Monday afternoon. Humidities will only be a little higher. A cold front will bring strong north winds and quick cooling Monday evening, with rain and snow developing by Tuesday morning. COZ238-242>251-070315- /O.EXP.KBOU.FW.W.0024.000000T0000Z-200907T0200Z/ Larimer County Below 6000 Feet/Northwest Weld County- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 813 PM MDT Sun Sep 6 2020 ...RED FLAG WARNING HAS EXPIRED FOR WIND AND LOW RELATIVE HUMIDITY FOR MUCH OF THE NORTHEAST PLAINS OF COLORADO... Conditions have moderated for the evening. On Monday, it will be hot again and breezy by afternoon. Humidities will be a little higher than they were today. $$ COZ211>213-215-217-218-071200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- Larimer and Boulder Counties Between 6000 and 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 813 PM MDT Sun Sep 6 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT MONDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS...HIGH MOUNTAIN VALLEYS...AND NORTHERN FRONT RANGE FOOTHILLS... * Affected Area...Fire Weather Zones 211...212...213...215... 217 and 218. * Winds...West 10 to 20 mph with gusts up to 35 mph. * Timing...Lighter winds but poor humidity recovery tonight, then warm and windy on Monday. * Relative Humidity...As low as 9 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ Gimmestad
340 WWUS85 KBOU 070958 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 358 AM MDT Mon Sep 7 2020 ...ONE MORE DAY OF EXTREME FIRE DANGER IN THE MOUNTAINS... COZ211>213-215-217-218-072200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- Larimer and Boulder Counties Between 6000 and 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 358 AM MDT Mon Sep 7 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS, HIGH MOUNTAIN VALLEYS, AND NORTHERN FRONT RANGE FOOTHILLS... * Affected Area...Fire Weather Zones 211, 212, 213, 215, 217, and 218. * Winds...West 15 to 25 mph with gusts up to 35 mph. * Timing...Through 8 PM MDT this evening. * Relative Humidity...As low as 7 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$
710 WWUS85 KBOU 071929 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 129 PM MDT Mon Sep 7 2020 ...ONE MORE DAY OF EXTREME FIRE DANGER IN THE MOUNTAINS... Westerly winds have increased over the mountains and ridges today as warm temperatures also continue. Fire behavior on the Cameron Peak Fire has been extreme today. Weather sensors near the fire have been reporting wind gusts up to 53 mph. Winds above Berthoud Pass have also gusted to a near 50 mph. Humidity levels have also been very low as the late summer airmass remains over the state today. The strong Canadian cold front that is expected to move over the region this evening is going to bring strong winds out of the north and then cooler temperatures by morning. Erratic fire behavior will continue through this evening. Cooler temperatures and higher humidity levels on Tuesday should begin easing the extreme fire conditions. COZ211>213-215-217-218-080200- /O.CON.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- Larimer and Boulder Counties Between 6000 and 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 129 PM MDT Mon Sep 7 2020 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR THE MOUNTAINS, HIGH MOUNTAIN VALLEYS, AND NORTHERN FRONT RANGE FOOTHILLS... * Affected Area...Fire Weather Zones 211...212...213...215... 217 and 218. * Winds...West 20 to 30 mph with gusts up to 50 mph. * Timing...Through 8 PM MDT this evening. * Relative Humidity...As low as 7 percent. * Impacts...Rapid growth of existing fires and new fire starts will be possible due to the gusty winds and very low humidity. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. The combination of strong winds...low relative humidity...and warm temperatures will continue contributing to extreme fire behavior. && $$
078 WWUS85 KBOU 080154 RFWBOU URGENT - FIRE WEATHER MESSAGE National Weather Service Denver/Boulder CO 754 PM MDT Mon Sep 7 2020 COZ211>213-215-217-218-080300- /O.CAN.KBOU.FW.W.0024.000000T0000Z-200908T0200Z/ Jackson County Below 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Grand and Summit Counties Below 9000 Feet- Larimer and Boulder Counties Between 6000 and 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- 754 PM MDT Mon Sep 7 2020 ...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT FOR THE THE MOUNTAINS, HIGH MOUNTAIN VALLEYS, AND NORTHERN FRONT RANGE FOOTHILLS... The National Weather Service in Denver has allowed the Red Flag Warning to expire this evening. A significant weather change is expected over all of north central and northeastern Colorado with significantly colder air and a significant snowfall for the next couple of days. The fire danger will hopefully ease considerably. $$
What forecasters said that day
The local office's own words before this red flag warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before this red flag warning went out at Sep 4, 11:11 AM MDT, 3 hours 29 minutes earlier.
Area forecast discussion, Sep 4, 11:11 AM MDT, 3 hours 29 minutes before
Area Forecast Discussion National Weather Service Denver/Boulder CO 1111 AM MDT Fri Sep 4 2020 .UPDATE... Issued at 1057 AM MDT Fri Sep 4 2020 Nary a cloud to be found over the CWA this morning. Latest model data keeps the low level winds pretty weak all day for all the CWA and there isn't much moisture either. Not much to alter this update. May up the highs a degree or two. && .SHORT TERM...(Today and tonight) Issued at 201 AM MDT Fri Sep 4 2020 The upper level ridge will be centered over NV/UT today with a weak and subsident northwesterly flow aloft. Temperatures will climb back into the lower 90s across the urban corridor and northeast plains. Weak pressure gradients at the surface coupled with the weak flow aloft will allow for light winds across the forecast area this afternoon. Clear and dry overnight. .LONG TERM...(Saturday through Thursday) Issued at 201 AM MDT Fri Sep 4 2020 ...RECORD HEAT THIS WEEKEND TO POSSIBLE SNOW TUESDAY... Upper level ridge centered over the Great Basin will retrograde westward Sunday over California and Nevada. By Monday, what's left of the ridge is just off the California coast. This ridge will keep it hot and dry Saturday and Sunday. Highs across northeast Colorado are expected to reach the mid 90s to lower 100s. A low pressure trough across eastern Colorado and a short wave trough passing to the north of Colorado will cause west to northwest winds to increase Sunday. This downslope flow will produce very dry conditions. It will likely offset any minor cooling associated with the short wave trough. A weak cold front drops south across the area Sunday night. Gusty east winds behind it are expected for Monday. This will usher in cooler air into northeast Colorado. For Monday, models still showing a strong open trough over the Northern Rockies. This trough then dives south and strengthens into a closed low over somewhere near the Four Corner Tuesday. A strong cold front associated with this system pushes south through the state late Monday afternoon through Monday night. Precipitation develops Monday evening and becomes widespread overnight Monday night and Tuesday. The 00Z GFS, GEM, and ECMWF are quite impressive with the amount of cold that accompanies this storm system. If the current solutions are right or close, it will be cold enough for snow to fall along the Front Range Urban Corridor and nearby plains. Accumulating snow on trees may cause considerable tree damage and related impacts will be possible. This system is four days away and models will likely change some. Confidence is becoming high that snow will occur in the mountains and foothills Monday night through Tuesday evening. A slight change in storm track or a slightly weaker closed low may keep the lower elevations warm enough for rain. Main message is cold and heavy snow is possible Monday night through Tuesday night. Monitor the latest forecasts and consider changing outdoor or travel plans if cold and snow still look on track. From Wednesday through Friday, the closed low gets cut off from the main flow aloft. Not much agreement on where the low meanders through the late weekend. Would expect temperatures to be well below normal. As far as PoPs goes, will have the highest PoPs Wednesday and then taper them down through the late week as the low will likely be weakening. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 1057 AM MDT Fri Sep 4 2020 Models have east, then southeasterly winds at DIA with normal drainage patterns by 04Z. No ceiling issues, in fact, no clouds, for the most part. && .FIRE WEATHER... Issued at 201 AM MDT Fri Sep 4 2020 The fire danger today will be elevated with above normal temperatures expected and minimum rh values in the teens. No dry thunderstorms and light winds however will help to offset the danger somewhat, therefore no highlights at this time. It will be hot and dry Saturday and Sunday with record to near record heat. Relative humidities are expected to fall to 5 to 12 percent during the afternoons. Winds become gusty Sunday afternoon and will increase the fire danger. A cold front will usher gusty easterly winds for Monday with higher relative humidities. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && UPDATE.........RJK SHORT TERM.....Cooper LONG TERM......Meier AVIATION.......RJK FIRE WEATHER...Meier
Hazardous weather outlook, Sep 4, 11:14 AM MDT, 3 hours 26 minutes before
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1114 AM MDT Fri Sep 4 2020 COZ030>051-051715- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1114 AM MDT Fri Sep 4 2020 ...Significant Change in the Weather Late Monday into Tuesday... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Dry conditions are expected today with above normal high temperatures. Winds will be pretty weak in most areas, but it will be quite warm and dry. As a result, fire danger will be elevated. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Record or near record heat combined with very dry conditions will result in elevated fire danger across the region through Sunday. Winds will increase Sunday into Monday when critical fire danger conditions may develop. A significant change in the weather will occur late Monday into Tuesday. Temperatures will plummet behind a strong cold front with rain and snow forming. Snow levels will drop sharply and accumulating snow is likely across the mountains and foothills. We are still watching the track of this next storm system and how much cold air arrives, but there is potential that the I-25 Corridor, including the Denver metro area, sees snow as well. If snow does fall, tree damage and power outages will be possible. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be be needed today and tonight.
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 4, 2:40 PM MDT | Fire Weather Watch | BOU | Adams, Arapahoe, Boulder, Elbert, Larimer, Lincoln and 6 more | 13 hr |
Nearby
Red Flag Warnings in Colorado, 2020Every red flag warning in 2020
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.