Alert archive / Colorado / Winter Storm Warnings in 2007

Winter Storm Warning 6, NWS Denver/Boulder, CO

October 20, 200712 counties in Colorado

NWS Denver/Boulder, CO issued this winter storm warning at Oct 20, 2007, 4:14 PM MDT for 12 counties in Colorado. It took effect at Oct 20, 2007, 6:00 PM MDT. It was in force for 22 hr. 34 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Oct 20, 2007, 4:14 PM MDT (22:14 UTC)
In effect from
Oct 20, 2007, 6:00 PM MDT
Expired
Oct 21, 2007, 3:34 PM MDT
In force
22 hr
Issued by
NWS Denver/Boulder, CO

Counties Arapahoe County, CO, Boulder County, CO, Clear Creek County, CO, Douglas County, CO, Elbert County, CO, Gilpin County, CO, Grand County, CO, Jackson County, CO, Jefferson County, CO, Larimer County, CO, Park County, CO, Summit County, CO

The radar

The Denver radar (KFTG), 74 km from the middle of the area, began a volume at 22:19 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.

What was reported inside it

TimeReportWhereRemark
Oct 21, 5:35 AM MDTHEAVY SNOW 6.51 Se Breckenridge, CO
Oct 21, 5:45 AM MDTSNOW 1Jefferson, CO
Oct 21, 5:45 AM MDTSNOW 1Lone Tree, CO
Oct 21, 5:45 AM MDTSNOW 1Sedalia, CO
Oct 21, 5:45 AM MDTSNOW 1.5Pine Junction, CO
Oct 21, 5:45 AM MDTSNOW 21 Ne Castle Rock, CO
Oct 21, 5:45 AM MDTSNOW 23 E Franktown, CO
Oct 21, 7:00 AM MDTSNOW 18 Sw Lake George, CO
Oct 21, 7:52 AM MDTSNOW 1.5Parker, CO
Oct 21, 8:00 AM MDTSNOW 1.3Evergreen, CO
Oct 21, 8:00 AM MDTSNOW 1.9Virginia Dale, CO
Oct 21, 8:00 AM MDTSNOW 21 E Dillon, CO
Oct 21, 8:00 AM MDTHEAVY SNOW 6Williams Fork Reservoir, CO
Oct 21, 8:23 AM MDTSNOW 2.5Greenwood Village, CO
Oct 21, 8:45 AM MDTSNOW 1.5Bailey, CO
Oct 21, 8:51 AM MDTSNOW 4.52 W Arapahoe Park, CO
Oct 21, 8:58 AM MDTSNOW 3.54 E Parker, CO
Oct 21, 9:00 AM MDTSNOW 4.52 Nw Elizabeth, CO
Oct 21, 9:00 AM MDTHEAVY SNOW 94 Se Gould, CO
Oct 21, 9:08 AM MDTSNOW 1Littleton, CO
Oct 21, 9:35 AM MDTSNOW 1.9Genesee, CO
Oct 21, 9:43 AM MDTSNOW 3.7Genesee, CO1.8 INCHES SNOW PAST HOUR
Oct 21, 10:55 AM MDTSNOW 44 E Parker, CO
Oct 21, 11:00 AM MDTHEAVY SNOW 6Centennial, CO
Oct 21, 11:30 AM MDTHEAVY SNOW 71 N Castle Rock, CO
Oct 21, 11:36 AM MDTHEAVY SNOW 6.36 Ssw Elizabeth, COONE TO TWO FOOT DRIFTS
Oct 21, 11:45 AM MDTSNOW 5.51 Nw Fraser, CO
Oct 21, 11:48 AM MDTSNOW 4.52 Wsw Highlands Ranch, CO
Oct 21, 12:20 PM MDTHEAVY SNOW 7.5Centennial, CO
Oct 21, 12:35 PM MDTHEAVY SNOW 6.91 Sw Lone Tree, CO
Oct 21, 12:45 PM MDTHEAVY SNOW 6Genesee, CO
Oct 21, 12:50 PM MDTHEAVY SNOW 7.34 E Parker, CO
Oct 21, 1:06 PM MDTHEAVY SNOW 7Greenwood Village, CO
Oct 21, 2:13 PM MDTSNOW 510 N Elizabeth, CO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.2 hours before the alert went out and 186 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.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2007-10-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2007-10-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -59 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3311 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-59 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS45 KBOU 202214
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
414 PM MDT SAT OCT 20 2007

...WINTER STORM MOVING INTO COLORADO...

.A COLD FRONT WILL MOVE ACROSS NORTHERN COLORADO THIS EVENING.
SNOW WILL BECOME WIDESPREAD ACROSS THE HIGHER MOUNTAINS EARLY THIS
EVENING...WITH RAIN AND SNOW DEVELOPING IN THE FRONT RANGE
FOOTHILLS. RAIN IS EXPECTED TO BREAK OUT ON THE PLAINS AROUND
MIDNIGHT BEHIND THE FRONT...BUT IT WILL CHANGE OVER TO SNOW OR A
MIXTURE OF RAIN AND SNOW ON THE PLAINS BY MORNING. PRECIPITATION
WILL GRADUALLY DECREASE DURING THE DAY ON SUNDAY...FAVORING NORTH
FACING SLOPES IN THE MOUNTAINS. ON THE PLAINS THERE WILL BE SNOW
IN MANY AREAS...BUT TEMPERATURES WILL BE WARM ENOUGH TO LIMIT SNOW
ACCUMULATIONS IN MOST AREAS. HOWEVER...UP TO 6 INCHES OF SNOW ARE
POSSIBLE IN THE HIGHER ELEVATIONS OF DOUGLAS AND WESTERN ELBERT
COUNTIES...INCLUDING ALONG INTERSTATE 25 OVER MONUMENT HILL.

COZ031-033-034-210615-
/O.UPG.KBOU.WS.A.0007.071021T0000Z-071022T0000Z/
/O.NEW.KBOU.WS.W.0006.071021T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 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-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS...
BERTHOUD PASS...BRECKENRIDGE...EAST SLOPES MOSQUITO RANGE...
EAST SLOPES SOUTHERN GORE RANGE...EISENHOWER TUNNEL...
INDIAN PEAKS...KENOSHA MOUNTAINS...MOUNT EVANS...
WILLIAMS FORK MOUNTAINS...WINTER PARK
414 PM MDT SAT OCT 20 2007

...WINTER STORM WARNING IN EFFECT UNTIL 6 PM MDT SUNDAY...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A WINTER STORM
WARNING...WHICH IS IN EFFECT UNTIL 6 PM MDT SUNDAY. THE WINTER
STORM WATCH IS NO LONGER IN EFFECT. 

SNOW WILL SPREAD ACROSS THE MOUNTAINS THIS EVENING AND WILL BE
HEAVY AT TIMES INTO SUNDAY. SNOW ACCUMULATIONS OF 8 TO 16 INCHES
ARE EXPECTED BY SUNDAY AFTERNOON. WEST TO NORTHWEST WINDS AT 15 TO 30 MPH
WITH GUSTS AS HIGH AS 40 MPH WILL PRODUCE EXTENSIVE BLOWING AND
DRIFTING SNOW IN EXPOSED AREAS.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS AND STRONG WINDS WILL MAKE TRAVEL VERY HAZARDOUS.

$$

COZ041-210615-
/O.NEW.KBOU.SB.Y.0016.071021T0900Z-071022T0000Z/
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...CASTLE ROCK...ELBERT...FONDIS...KIOWA...LARKSPUR
414 PM MDT SAT OCT 20 2007

...SNOW AND BLOWING SNOW ADVISORY IN EFFECT FROM 3 AM TO 6 PM MDT
SUNDAY...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SNOW AND
BLOWING SNOW ADVISORY...WHICH IS IN EFFECT FROM 3 AM TO 6 PM MDT
SUNDAY. 

SNOW WILL DEVELOP OVER THE HIGHER ELEVATIONS SOUTH OF DENVER LATE
TONIGHT AND CONTINUE THROUGH MUCH OF THE DAY SUNDAY. UP TO 6
INCHES OF SNOWFALL IS EXPECTED...WITH THE HIGHER AMOUNTS IN
SOUTHERN DOUGLAS AND SOUTHWEST ELBERT COUNTIES. NORTH WINDS AT 20
TO 30 MPH WILL ALSO PRODUCE AREAS OF BLOWING SNOW. WHILE WARM
GROUND TEMPERATURES WILL LIMIT ACCUMULATIONS ON PAVEMENT...ROADS
WILL LIKELY BECOME SLUSHY. BLOWING AND DRIFTING SNOW MAY ALSO
LIMIT VISIBILITY.

TRAVELERS ARE URGED TO PLAN FOR WINTER TRAVEL CONDITIONS ON
SUNDAY IN THE MONUMENT HILL AREA.

$$

GIMMESTAD
5 follow-up statements
000 
WWUS45 KBOU 210215
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
815 PM MDT SAT OCT 20 2007

...WIND...COLD AND SNOW HEADING FOR NORTHEAST COLORADO...

.TWO STRONG COLD FRONTS...ONE QUICKLY MOVING ACROSS THE NORTH
CENTRAL MOUNTAINS OF COLORADO...AND A SECOND FRONT DROPPING SOUTH
ACROSS NORTHEAST COLORADO WILL CONVERGE ON THE COLORADO FRONT
RANGE URBAN CORRIDOR BEFORE MIDNIGHT TONIGHT. SNOW WAS ALREADY
FALLING HEAVY AT TIMES ALONG AND WEST OF THE CONTINENTAL DIVIDE.
WHILE RAIN WAS SPREADING SOUTH OUT OF NEBRASKA. RAIN AND SNOW
WILL DEVELOP ACROSS THE PLAINS OF NORTHEAST COLORADO BEFORE
MIDNIGHT AS SNOW SPREADS DOWN THE FRONT RANGE. GUSTY NORTH WINDS
WILL ALSO USHER IN MUCH COLDER AIR WHICH SHOULD CHANGE ANY RAIN TO
ALL SNOW IN AREAS NEAR THE FOOTHILLS AND OVER THE PALMER DIVIDE
NOT LONG AFTER MIDNIGHT. IN THE HIGH COUNTRY...STRONG NORTHWEST
WINDS WILL ALSO PRODUCE CONSIDERABLE BLOWING AND DRIFTING
SNOW...ESPECIALLY ON THE HIGH MOUNTAIN PASSES. SNOWFALL WILL
LINGER THROUGHOUT THE DAY ON SUNDAY IN THE MOUNTAINS...WITH
SEVERAL INCHES OF ADDITIONAL ACCUMULATION PARTICULARLY ON
NORTHWEST FACING SLOPES. ON THE HIGH PLAINS PRECIPITATION WILL
GRADUALLY DECREASE DURING THE DAY AS THE STORM SYSTEM MOVES AWAY.
LIGHT SNOW ACCUMULATION IS ANTICIPATED AT LOWER ELEVATIONS...WITH
UPWARDS OF 6 INCHES ON THE PALMER DIVIDE EXPECTED BY LATE IN THE
AFTERNOON. ELSEWHERE...WARM GROUND TEMPERATURES WILL LIKELY LIMIT
SNOW ACCUMULATIONS.

COZ031-033-034-211015-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 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-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS...
BERTHOUD PASS...BRECKENRIDGE...EAST SLOPES MOSQUITO RANGE...
EAST SLOPES SOUTHERN GORE RANGE...EISENHOWER TUNNEL...
INDIAN PEAKS...KENOSHA MOUNTAINS...MOUNT EVANS...
WILLIAMS FORK MOUNTAINS...WINTER PARK
815 PM MDT SAT OCT 20 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT SUNDAY FOR 
THE NORTH CENTRAL MOUNTAINS AND HIGH VALLEYS OF COLORADO...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT SUNDAY. 

SNOW WILL BECOME HEAVY AT TIMES IN THE MOUNTAINS AND HIGH VALLEYS
OF NORTH CENTRAL COLORADO OVERNIGHT. SNOW MAY BE ACCOMPANIED BY
A FEW THUNDERSTORMS BEFORE MIDNIGHT. SNOW WILL CONTINUE TO FALL
THROUGH THE DAY SUNDAY...HEAVY AT TIMES...WITH TOTAL SNOW
ACCUMULATIONS RANGING FROM 8 TO 16 INCHES BY LATE AFTERNOON. WEST
TO NORTHWEST WINDS AT 20 TO 30 MPH WITH GUSTS AS HIGH AS 50 MPH
WILL ALSO PRODUCE EXTENSIVE BLOWING AND DRIFTING SNOW IN EXPOSED
AREAS.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS AND STRONG WINDS WILL MAKE TRAVEL VERY HAZARDOUS.

$$

COZ041-211015-
/O.CON.KBOU.SB.Y.0016.071021T0900Z-071022T0000Z/
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...CASTLE ROCK...ELBERT...FONDIS...KIOWA...LARKSPUR
815 PM MDT SAT OCT 20 2007

...SNOW AND BLOWING SNOW ADVISORY REMAINS IN EFFECT FROM 3 AM TO
6 PM MDT SUNDAY FOR THE PALMER DIVIDE IN EAST CENTRAL COLORADO...

A SNOW AND BLOWING SNOW ADVISORY REMAINS IN EFFECT FROM 3 AM TO
6 PM MDT SUNDAY. 

SNOW WILL DEVELOP OVER THE HIGHER TERRAIN KNOWN AS THE PALMER
DIVIDE SOUTH OF DENVER LATE TONIGHT AND CONTINUE THROUGH MUCH OF
THE DAY ON SUNDAY. UP TO 6 INCHES OF SNOW ACCUMULATION IS
EXPECTED...WITH THE HIGHER AMOUNTS IN SOUTHERN DOUGLAS AND
SOUTHWEST ELBERT COUNTIES. NORTH WINDS AT 20 TO 30 MPH WILL ALSO
PRODUCE AREAS OF BLOWING SNOW. WHILE WARM GROUND TEMPERATURES WILL
LIMIT ACCUMULATIONS ON PAVEMENT...ROADS WILL LIKELY BECOME SLUSHY.
BLOWING AND DRIFTING SNOW MAY ALSO LIMIT VISIBILITY.

TRAVELERS ARE URGED TO PLAN FOR WINTER TRAVEL CONDITIONS ON
SUNDAY IN THE MONUMENT HILL AREA.

$$
BAKER
000 
WWUS45 KBOU 210453
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
1053 PM MDT SAT OCT 20 2007

COZ041-211300-
/O.UPG.KBOU.SB.Y.0016.071021T0900Z-071022T0000Z/
/O.EXB.KBOU.WS.W.0006.071021T0600Z-071022T0000Z/
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...CASTLE ROCK...ELBERT...FONDIS...KIOWA...LARKSPUR
1053 PM MDT SAT OCT 20 2007

...WINTER STORM WARNING IN EFFECT UNTIL 6 PM MDT SUNDAY FOR THE 
PALMER DIVIDE IN EAST CENTRAL COLORADO...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A WINTER STORM
WARNING...WHICH IS IN EFFECT UNTIL 6 PM MDT SUNDAY. THE SNOW AND
BLOWING SNOW ADVISORY IS NO LONGER IN EFFECT. 

SNOW WILL DEVELOP OVER THE HIGHER TERRAIN KNOWN AS THE PALMER
DIVIDE SOUTH OF DENVER AROUND MIDNIGHT TONIGHT AND CONTINUE
THROUGH MUCH OF THE DAY ON SUNDAY. TOTAL SNOW ACCUMULATION OF 5 TO
10 INCHES IS EXPECTED BY LATE SUNDAY AFTERNOON...WITH THE GREATER 
AMOUNTS OVER THE HIGHER ELEVATIONS IN SOUTHERN DOUGLAS AND
SOUTHWEST ELBERT COUNTIES. NORTH WINDS AT 20 TO 30 MPH WITH GUSTS
TO AROUND 40 MPH WILL ALSO PRODUCE AREAS OF BLOWING SNOW LATE IN
THE MORNING AND AFTERNOON ON SUNDAY. THE BLOWING AND DRIFTING
SNOW MAY SIGNIFICANTLY LIMIT VISIBILITY.

TRAVELERS ARE URGED TO PLAN FOR HAZARDOUS WINTER TRAVEL
CONDITIONS LATE TONIGHT AND SUNDAY IN THE MONUMENT HILL AREA.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS ARE OCCURRING OR EXPECTED. STRONG WINDS ARE ALSO
POSSIBLE. THIS WILL MAKE TRAVEL VERY HAZARDOUS OR IMPOSSIBLE.

$$

COZ035-036-211300-
/O.EXA.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
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-
INCLUDING...ESTES PARK...GLENDEVEY...NEDERLAND...
RED FEATHER LAKES...BAILEY...CENTRAL CITY...EVERGREEN...
GEORGETOWN...IDAHO SPRINGS...WESTCREEK
1053 PM MDT SAT OCT 20 2007

...WINTER STORM WARNING IN EFFECT UNTIL 6 PM MDT SUNDAY FOR THE 
COLORADO FRONT RANGE FOOTHILLS...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A WINTER STORM
WARNING...WHICH IS IN EFFECT UNTIL 6 PM MDT SUNDAY. 

SNOW WILL BECOME HEAVY AT TIMES IN THE FRONT RANGE FOOTHILLS 
OVERNIGHT. TOTAL SNOW ACCUMULATIONS BY SUNDAY AFTERNOON WILL RANGE
FROM 5 TO 9 INCHES WITH UP TO A FOOT OF SNOW IN THE FOOTHILLS
SOUTHWEST OF DENVER. NORTHWEST WINDS AT 20 TO 30 MPH WITH GUSTS TO
40 MPH WILL ALSO PRODUCE BLOWING AND DRIFTING SNOW IN EXPOSED
AREAS ON SUNDAY.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS AND STRONG WINDS WILL MAKE TRAVEL VERY HAZARDOUS.

$$

COZ031-033-034-211300-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 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-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS...
BERTHOUD PASS...BRECKENRIDGE...EAST SLOPES MOSQUITO RANGE...
EAST SLOPES SOUTHERN GORE RANGE...EISENHOWER TUNNEL...
INDIAN PEAKS...KENOSHA MOUNTAINS...MOUNT EVANS...
WILLIAMS FORK MOUNTAINS...WINTER PARK
1053 PM MDT SAT OCT 20 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT SUNDAY 
FOR THE NORTH CENTRAL MOUNTAINS OF COLORADO...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT SUNDAY. 

SNOW WILL HEAVY AT TIMES IN THE NORTH CENTRAL MOUNTAINS OF
COLORADO OVERNIGHT AND THROUGH MOST OF THE DAY SUNDAY. TOTAL SNOW
ACCUMULATIONS BY LATE SUNDAY AFTERNOON WILL RANGE FROM 8 TO 16
INCHES...WITH THE GREATER AMOUNTS ON NORTHWEST FACING SLOPES. WEST
TO NORTHWEST WINDS AT 20 TO 30 MPH WITH GUSTS AS HIGH AS 50 MPH
WILL ALSO PRODUCE EXTENSIVE BLOWING AND DRIFTING SNOW IN EXPOSED
AREAS.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS AND STRONG WINDS WILL MAKE TRAVEL VERY HAZARDOUS.

$$

COZ030-032-211300-
/O.NEW.KBOU.SN.Y.0013.071021T0453Z-071022T0000Z/
JACKSON COUNTY BELOW 9000 FEET-
GRAND AND SUMMIT COUNTIES BELOW 9000 FEET-
INCLUDING...GOULD...NORTH PARK...RAND...SPICER...WALDEN...
DILLON...FRASER...GRANBY...GRAND LAKE...HOT SULPHUR SPRINGS...
KREMMLING
1053 PM MDT SAT OCT 20 2007

...SNOW ADVISORY IN EFFECT UNTIL 6 PM MDT SUNDAY FOR THE HIGH 
MOUNTAIN VALLEYS IN NORTH CENTRAL COLORADO...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SNOW
ADVISORY...WHICH IS IN EFFECT UNTIL 6 PM MDT SUNDAY. 

SNOW...POSSIBLY HEAVY AT TIMES...CAN BE EXPECTED IN THE HIGH
MOUNTAIN VALLEYS OVERNIGHT AND THROUGH MUCH OF THE DAY ON SUNDAY.
TOTAL SNOW ACCUMULATIONS BY SUNDAY AFTERNOON WILL RANGE FROM 4 TO 8
INCHES WITH THE GREATER AMOUNTS NEAR NORTHWEST FACING MOUNTAIN
SLOPES.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE SOME TRAVEL
DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND LIMITED
VISIBILITIES...AND USE CAUTION WHILE DRIVING.

$$
BAKER
000 
WWUS45 KBOU 211101
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
501 AM MDT SUN OCT 21 2007

...STORM SYSTEM WILL MOVE ACROSS COLORADO TODAY WITH SNOW...

.AFTER A LULL IN THE SNOWFALL OVERNIGHT...SNOW WILL REDEVELOP AND
BECOME MORE WIDESPREAD AND HEAVIER ACROSS NORTHEAST AND NORTH
CENTRAL COLORADO THIS MORNING. UPSLOPE FLOW WILL DEVELOP...WHICH
IS STILL EXPECTED TO PRODUCE A PERIOD OF HEAVY SNOWFALL IN THE
FRONT RANGE MOUNTAINS AND FOOTHILLS. SOME OF THIS SNOW WILL SPREAD
EASTWARD ACROSS THE FRONT RANGE URBAN CORRIDOR...WITH A RAIN AND
SNOW MIX FALLING ACROSS THE NORTHEASTERN PLAINS OF COLORADO.

COZ031-033-034-211915-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 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-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS...
BERTHOUD PASS...BRECKENRIDGE...EAST SLOPES MOSQUITO RANGE...
EAST SLOPES SOUTHERN GORE RANGE...EISENHOWER TUNNEL...
INDIAN PEAKS...KENOSHA MOUNTAINS...MOUNT EVANS...
WILLIAMS FORK MOUNTAINS...WINTER PARK
501 AM MDT SUN OCT 21 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. 

SNOW WILL INCREASE IN COVERAGE AND INTENSITY ACROSS THE MOUNTAINS
THIS MORNING...AND MAY BECOME HEAVY AT TIMES ALONG THE FRONT
RANGE. THE SNOW WILL THEN DIMINISH DURING THE LATE AFTERNOON
HOURS. TOTAL ACCUMULATIONS OF 6 TO 14 INCHES CAN BE EXPECTED. 

NORTH WINDS OF 15 TO 25 MPH ABOVE TIMBERLINE...WITH GUSTS AS HIGH
AS 40 MPH...WILL PRODUCE AREAS OF BLOWING AND DRIFTING SNOW.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS AND STRONG WINDS WILL MAKE TRAVEL HAZARDOUS.

$$

COZ035-036-211915-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
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-
INCLUDING...ESTES PARK...GLENDEVEY...NEDERLAND...
RED FEATHER LAKES...BAILEY...CENTRAL CITY...EVERGREEN...
GEORGETOWN...IDAHO SPRINGS...WESTCREEK
501 AM MDT SUN OCT 21 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. 

SNOW WILL SPREAD SOUTHWARD ACROSS THE FRONT RANGE FOOTHILLS THIS
MORNING AND MAY BECOME HEAVY AT TIMES. THE SNOW WILL THEN DIMINISH
DURING THE LATE AFTERNOON HOURS. TOTAL ACCUMULATIONS OF 4 TO 9
INCHES CAN BE EXPECTED...WITH SLIGHTLY HIGHER AMOUNTS POSSIBLE IN
THE FOOTHILLS OF SOUTHERN JEFFERSON AND DOUGLAS COUNTIES. 

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS WILL MAKE TRAVEL HAZARDOUS.

$$

COZ041-211915-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...CASTLE ROCK...ELBERT...FONDIS...KIOWA...LARKSPUR
501 AM MDT SUN OCT 21 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. 

SNOW WILL CONTINUE OVER THE PALMER DIVIDE AREA THROUGH THE EARLY
AFTERNOON HOURS...AND MAY BE HEAVY AT TIMES. TOTAL SNOW
ACCUMULATIONS OF 4 TO 8 INCHES CAN BE EXPECTED BEFORE THE SNOW
DECREASES LATE THIS AFTERNOON.

REMEMBER...A WINTER STORM WARNING MEANS HAZARDOUS WINTER WEATHER
CONDITIONS ARE IMMINENT OR HIGHLY LIKELY. SIGNIFICANT SNOW
ACCUMULATIONS ARE OCCURRING OR EXPECTED. TRAVEL WILL BE HAZARDOUS
ESPECIALLY OVER THE MONUMENT HILL AREA.

$$

COZ030-032-211915-
/O.CON.KBOU.SN.Y.0013.000000T0000Z-071022T0000Z/
JACKSON COUNTY BELOW 9000 FEET-
GRAND AND SUMMIT COUNTIES BELOW 9000 FEET-
INCLUDING...GOULD...NORTH PARK...RAND...SPICER...WALDEN...
DILLON...FRASER...GRANBY...GRAND LAKE...HOT SULPHUR SPRINGS...
KREMMLING
501 AM MDT SUN OCT 21 2007

...SNOW ADVISORY REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A SNOW ADVISORY REMAINS IN EFFECT UNTIL 6 PM MDT THIS AFTERNOON. 

PERIODS OF SNOW CAN BE EXPECTED UNTIL EARLY AFTERNOON...THEN SNOW
WILL DECREASE. TOTAL ACCUMULATIONS WILL RANGE BETWEEN 4 AND 8 INCHES.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE SOME TRAVEL
DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND LIMITED
VISIBILITIES...AND USE CAUTION WHILE DRIVING.

$$

BARJENBRUCH
000 
WWUS45 KBOU 211717
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
1117 AM MDT SUN OCT 21 2007

...WINTER STORM CONTINUES ACROSS NORTHERN COLORADO...

.AREAS OF HEAVY SNOW DEVELOPED IN THE FRONT RANGE FOOTHILLS AND
JUST SOUTH OF DENVER THIS MORNING AS A WINTER STORM MOVED ONTO THE
PLAINS. SNOWFALL RATES OF 1 TO 3 INCHES PER HOUR HAVE BEEN
REPORTED IN THE FOOTHILLS WEST OF DENVER...AND IN THE SOUTHERN
SUBURBS OF DENVER. SOME SNOWFALL AMOUNTS INCLUDE 6 INCHES AT
CENTENNIAL AIRPORT AND 4 INCHES AT GENESSEE. IN THESE AREAS THE
SNOW IS EXPECTED TO DECREASE IN INTENSITY BY EARLY AFTERNOON...AND
END BY EARLY EVENING. MEANWHILE...FROM THE NORTH SIDE OF DENVER
NORTHWARD LITTLE OR NO ACCUMULATION HAS OCCURRED. 

IN THE MOUNTAINS MODERATE TO HEAVY SNOW CONTINUES IN AREAS NORTH
OF INTERSTATE 70...BUT ONLY LIGHT SNOW HAS FALLEN THIS MORNING IN
SUMMIT COUNTY AND IN NORTH AND MIDDLE PARKS. STORM TOTAL SNOWFALL
IN THESE AREAS HAS GENERALLY BEEN 3 TO 8 INCHES...WITH 11 INCHES ON
RABBIT EARS PASS. THE SNOW IS EXPECTED TO DECREASE IN THESE AREAS
THIS AFTERNOON AS WELL.

ROADS ARE GENERALLY WET OR SLUSHY BELOW 7500 FEET...BUT THERE ARE
SNOWPACKED OR ICY CONDITIONS ON HIGHWAYS IN THE HIGHER MOUNTAINS.
FOR THE LATEST ROAD CONDITIONS CALL 511.

COZ034>036-220000-
/O.CAN.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
/O.NEW.KBOU.SB.Y.0017.071021T1717Z-071022T0000Z/
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-
INCLUDING...BERTHOUD PASS...BRECKENRIDGE...
EAST SLOPES MOSQUITO RANGE...EAST SLOPES SOUTHERN GORE RANGE...
EISENHOWER TUNNEL...INDIAN PEAKS...KENOSHA MOUNTAINS...
MOUNT EVANS...WILLIAMS FORK MOUNTAINS...WINTER PARK...
ESTES PARK...GLENDEVEY...NEDERLAND...RED FEATHER LAKES...BAILEY...
CENTRAL CITY...EVERGREEN...GEORGETOWN...IDAHO SPRINGS...WESTCREEK
1117 AM MDT SUN OCT 21 2007

...SNOW AND BLOWING SNOW ADVISORY IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...
...WINTER STORM WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SNOW AND
BLOWING SNOW ADVISORY...WHICH IS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. THE WINTER STORM WARNING HAS BEEN CANCELLED. 

MODERATE TO HEAVY SNOW WILL CONTINUE THROUGH MIDDAY...THEN
DIMINISH DURING THE AFTERNOON. STORM TOTAL ACCUMULATIONS OF 4 TO 9
INCHES ARE EXPECTED...WITH THE HIGHEST AMOUNTS IN THE FOOTHILLS
WEST AND SOUTHWEST OF DENVER AND IN SUMMIT COUNTY. 

A SNOW AND BLOWING SNOW ADVISORY MEANS THAT VISIBILITIES WILL BE
LIMITED DUE TO A COMBINATION OF FALLING AND BLOWING SNOW. ROADS
WILL BE SLUSHY OR SNOWPACKED...WITH THE WORST CONDITIONS ABOVE
7500 FEET IN ELEVATION. 

$$

COZ030-032-211830-
/O.CAN.KBOU.SN.Y.0013.000000T0000Z-071022T0000Z/
JACKSON COUNTY BELOW 9000 FEET-
GRAND AND SUMMIT COUNTIES BELOW 9000 FEET-
INCLUDING...GOULD...NORTH PARK...RAND...SPICER...WALDEN...
DILLON...FRASER...GRANBY...GRAND LAKE...HOT SULPHUR SPRINGS...
KREMMLING
1117 AM MDT SUN OCT 21 2007

...SNOW ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN DENVER HAS CANCELLED THE SNOW
ADVISORY. 

SNOWFALL THIS AFTERNOON IS EXPECTED TO BE LIGHT WITH ADDITIONAL
ACCUMULATIONS OF AN INCH OR TWO. 

$$

COZ031-033-220000-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 9000 FEET-
SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/
NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS
1117 AM MDT SUN OCT 21 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. 

MODERATE TO HEAVY SNOW WILL CONTINUE THROUGH EARLY
AFTERNOON...ESPECIALLY ON NORTH FACING MOUNTAIN AREAS. SNOWFALL
WILL DECREASE CONSIDERABLY LATE THIS AFTERNOON. TOTAL
ACCUMULATIONS OF 8 TO 16 INCHES CAN BE EXPECTED.

NORTH WINDS OF 15 TO 25 MPH ABOVE TIMBERLINE...WITH GUSTS AS HIGH
AS 40 MPH...WILL PRODUCE AREAS OF BLOWING AND DRIFTING SNOW.

ROAD CONDITIONS AT HIGHER ELEVATIONS WILL REMAIN HAZARDOUS WITH
ICY OR SNOWPACKED ROADS AND LIMITED VISIBILITIES.

$$

COZ041-220000-
/O.CON.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...CASTLE ROCK...ELBERT...FONDIS...KIOWA...LARKSPUR
1117 AM MDT SUN OCT 21 2007

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS
AFTERNOON. 

SNOW INTENSITIES WILL DECREASE THIS AFTERNOON WITH SNOW ENDING BY
EARLY EVENING. TOTAL SNOW ACCUMULATIONS OF 4 TO 8 INCHES CAN BE
EXPECTED.

WHILE MOST ROADS IN THE AREA ARE SLUSHY...ELEVATIONS ABOVE 7500
FEET OR LESS TRAVELED ROADS MAY BECOME SNOWPACKED WITH SOME
DRIFTING IN SOUTHERN PARTS OF DOUGLAS AND ELBERT COUNTY. IF YOU
ARE TRAVELING IN RURAL PARTS OF THESE COUNTIES...BE PREPARED FOR
WINTER DRIVING CONDITIONS.

$$

GIMMESTAD
000 
WWUS45 KBOU 212134
WSWBOU

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE DENVER CO
334 PM MDT SUN OCT 21 2007

COZ031-033-041-212245-
/O.CAN.KBOU.WS.W.0006.000000T0000Z-071022T0000Z/
WEST JACKSON AND WEST GRAND COUNTIES ABOVE 9000 FEET-
SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/
NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-
ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-
INCLUDING...EAST SLOPES PARK AND NORTHERN GORE RANGES...
GORE PASS...RABBIT EARS PASS...CAMERON PASS...
LARAMIE AND MEDICINE BOW MOUNTAINS...RABBIT EARS RANGE...
ROCKY MOUNTAIN NATIONAL PARK...WILLOW CREEK PASS...CASTLE ROCK...
ELBERT...FONDIS...KIOWA...LARKSPUR
334 PM MDT SUN OCT 21 2007

...WINTER STORM WARNING IS CANCELLED FOR PORTIONS OF THE NORTHERN 
MOUNTAINS AND PALMER DIVIDE IN COLORADO...

THE NATIONAL WEATHER SERVICE IN DENVER HAS CANCELLED THE WINTER
STORM WARNING. 

ADDITIONAL SNOW ACCUMULATION IS NO LONGER ANTICIPATED IN THE NORTHERN
MOUNTAINS OR THE PALMER DIVIDE IN EAST CENTRAL COLORADO. THE
WINTER-LIKE STORM SYSTEM THAT DEPOSITED SEVERAL INCHES OF WIND 
BLOWN SNOW IN THESE AREAS LAST NIGHT AND THIS MORNING HAS MOVES
OUT OF THE AREA.


$$

COZ034>036-212245-
/O.CAN.KBOU.SB.Y.0017.000000T0000Z-071022T0000Z/
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-
INCLUDING...BERTHOUD PASS...BRECKENRIDGE...
EAST SLOPES MOSQUITO RANGE...EAST SLOPES SOUTHERN GORE RANGE...
EISENHOWER TUNNEL...INDIAN PEAKS...KENOSHA MOUNTAINS...
MOUNT EVANS...WILLIAMS FORK MOUNTAINS...WINTER PARK...
ESTES PARK...GLENDEVEY...NEDERLAND...RED FEATHER LAKES...BAILEY...
CENTRAL CITY...EVERGREEN...GEORGETOWN...IDAHO SPRINGS...WESTCREEK
334 PM MDT SUN OCT 21 2007

...SNOW AND BLOWING SNOW ADVISORY IS CANCELLED FOR THE NORTH CENTRAL 
MOUNTAINS AND THE FRONT RANGE FOOTHILLS OF COLORADO...

THE NATIONAL WEATHER SERVICE IN DENVER HAS CANCELLED THE SNOW AND
BLOWING SNOW ADVISORY. 

SNOWFALL HAS PRETTY MUCH ENDED AND WIND SPEEDS WILL CONTINUE TO
DECREASE IN THE NORTH CENTRAL MOUNTAINS AND FRONT RANGE FOOTHILLS
OF COLORADO THROUGH THE REMAINDER OF THE AFTERNOON. THE WINTER-
LIKE STORM SYSTEM THAT DEPOSITED SEVERAL INCHES OF SNOW IN THESE
AREAS LATE LAST NIGHT AND THIS MORNING HAS MOVES OUT OF THE AREA.


$$
BAKER

What forecasters said that day

The local office's own words before this winter storm 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 winter storm warning went out at Oct 20, 2:40 PM MDT, 1 hour 34 minutes earlier.

Area forecast discussion, Oct 20, 2:40 PM MDT, 1 hour 34 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
240 PM MDT SAT OCT 20 2007

.SHORT TERM...STARTING TO SEE SOME CONVERGENCE IN THE MODEL
SOLUTIONS AS THE NAM IS GETTING A LITTLE MORE AMPLIFIED WITH THE
INCOMING TROUGH AND SHOWING A FEW HOURS OF NNE LOW LEVEL FLOW ALONG
THE FRONT RANGE SUNDAY MORNING. MEANWHILE THE GFS IS ONLY SLIGHTLY
SLOWER. LOOKING AT THE CURRENT DEVELOPMENT OF THE TROUGH IT IS HARD
TO TELL WHICH IS BETTER...SO I WILL GO WITH A COMPROMISE.

SURFACE FRONT SHOULD PASS THROUGH DENVER THIS EVENING WITH COLD AIR
RUSHING IN A BIT AHEAD OF THE UPPER LEVEL TROUGH AND SHOWER BAND.
RAISED POPS AS THE LARGE SCALE FEATURE IS LOOKING GOOD FOR A BAND OF
PRECIP PASSING DURING THE EARLY MORNING HOURS. MAIN ADJUSTMENT I
WILL MAKE IS TO BACK OFF OF SNOW ACCUMULATIONS FOR ELEVATIONS BELOW
5000 FEET AS WARM AIR AND GROUND TEMPERATURES WILL MAKE ACCUMULATION
DIFFICULT. MODEL SOUNDINGS FROM NAM AND GFS SUGGEST SNOW LEVELS
DROPPING TO 4-5 THOUSAND FEET THIS MORNING AND STAYING THERE THROUGH
THE DAY SUNDAY. AIR TEMPERATURES IN DENVER WILL LIKELY STAY BELOW
FREEZING AND SHALLOW SOIL TEMPERATURES ARE IN THE 50S...SO LOTS OF
MELTING WITH THIS SYSTEM AND ACCUMULATIONS ON ROADS ARE LOOKING
UNLIKELY. COMBINATION OF HEAVIER SNOW AND COOLER TEMPERATURES MAY
MEAN MONUMENT HILL AND CHEYENNE RIDGE COULD GET SLUSHY...AND OF
COURSE THE FOOTHILLS ARE A DIFFERENT STORY. NNE FLOW FAVORS ZONE 41
AT LEAST AS MUCH AS THE FOOTHILLS...I WILL ISSUE A SNOW/BLOWING SNOW
ADVISORY FOR THAT AREA. FOOTHILLS HAVE HIGHER CRITERIA AND WILL HOLD
OFF THERE.

FOR THE HIGH MOUNTAINS...LOOKS LIKE A DECENT PERIOD OF GOOD
OROGRAPHICS WITH NEUTRAL STABILITY. WILL GO AHEAD WITH A WARNING
THOUGH AMOUNTS LOOK BORDERLINE...AROUND A FOOT IN 24 HOURS. THE END
OF THE EVENT WILL FAVOR NORTH FACING SLOPES AND WE MAY NEED TO WATCH
NORTH PARK AND MAYBE EVEN NORTHERN LARIMER COUNTY IF SUNDAY TURNS
OUT TO BE MORE PRODUCTIVE THAN EXPECTED.

.LONG TERM...MODELS HAVE THE UPPER TROUGH AXIS MOVE EAST ACROSS THE
FORECAST AREA SUNDAY NIGHT.  AGAIN...THE GFS IS ABOUT SIX HOURS
SLOWER THAN THE NAM.  ON MONDAY...THE VERY STRONG
NORTH-NORTHEASTERLY FLOW ALOFT WILL COVER THE FORECAST AREA.  THE
GFS HAS THE JET MAX AT 165 KNOTS OVER THE NORTHEAST CORNER MONDAY
AFTERNOON...THE NAM SHOWS 145 KNOTS AT THAT TIME.  THE FLOW RELAXES
SIGNIFICANTLY MONDAY NIGHT...CONTINUING TUESDAY...BUT THE GFS HANGS
ON TO DUE NORTHERLY FLOW INTO TUESDAY NIGHT...THE NAM SHOWS IT ALL
TO BE NORTHWESTERLY.  BOTH HAVE THE UPSTREAM RIDGE CENTERED OVER
GREAT BASIN LATE TUESDAY AFTERNOON.  THE QG VERTICAL VELOCITY FIELDS
HAVE STRONG DOWNWARD MOTION OVER THE FORECAST AREA SUNDAY
NIGHT...ITS STILL DOWNWARD ON MONDAY THROUGH TUESDAY BUT PRETTY
WEAK.  THE BOUNDARY LAYER FLOW IS PROGGED TO BE ALL DOWNSLOPING
SUNDAY NIGHT WELL INTO TUESDAY.  FOR MOISTURE...BOTH MODELS DRY US
OUT SUNDAY NIGHT BUT AT DIFFERENT RATES.  THE GFS IS SLOWER WITH THE
SYNOPTIC SCALE FEATURES...YET THE QUICKER NAM KEEPS THE MOISTURE
AROUND LONGER SUNDAY NIGHT.  FROM MONDAY ON...IT IS PRETTY DRY.
THERE MAY BE ENOUGH LINGERING MOISTURE IN THE HIGH MOUNTAINS TO
WARRANT MINIMAL POPS FOR SOME OF MONDAY.  FOR SUNDAY NIGHTS
POPS...WILL TAPPER OFF THE PRECIPITATION MAINLY DURING THE EVENING
HOURS.  WILL LET THE HIGH ALPINE MINIMAL POPS GOING ALL NIGHT.   FOR
TEMPERATURES...MONDAY ONLY WARMS SOME 2-3 C FROM SUNDAYS HIGH.
TUESDAYS THICKNESS GRIDS SHOW A 7-10 C WARM UP FROM MONDAY.

FOR THE LATER DAYS...WEDNESDAY THROUGH SATURDAY...THE MODELS SHOW
THE UPPER RIDGE OVER THE GREAT BASIN LATE ON TUESDAY...CREEPING
SLOWLY EASTWARD INTO THURSDAY...THEN IT FLATTENS SOME AND MOVES MORE
SOUTH OF THE FORECAST AREA FOR FRIDAY.  THE GFS AND ECMWF NOW SHOW
THE UPPER CLOSED LOW STALLING AROUND THE MEMPHIS AREA WEDNESDAY AND
THURSDAY.  THERE IS AN UPPER TROUGH TO OUR NORTH THAT FLATTENS THE
UPPER RIDGE LATER IN THE PERIOD.  THIS TROUGH HELPS A COLD FRONT AND
SHALLOW UPSLOPE MOVE INTO THE PLAINS THURSDAY NIGHT INTO FRIDAY.
BOTH THE GFS AND ECMWF HAVE THIS.  WILL COOL FRIDAY OFF A BIT...BUT
NO POPS YET...MOISTURE IS QUITE SPARSE THROUGH SATURDAY.

&&

.AVIATION...WEST WINDS GUSTING OF 20-30 KT WILL REACH DIA DURING THE
LATE AFTERNOON AND EVENING...THEN SHIFT TO NORTH AS A COLD FRONT
PASSES THROUGH THE DENVER AREA AROUND 02Z. RAIN WILL DEVELOP AFTER
MIDNIGHT...AND CHANGE TO SNOW IN THE DENVER AREA BY MORNING. THE
SNOW WILL DIMINISH IN THE AFTERNOON. AIR TEMPERATURES ARE EXPECTED
TO REMAIN AT OR ABOVE FREEZING...AND WARM GROUND WILL LIKELY PREVENT
SNOW ACCUMULATION ON PAVEMENT.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...RED FLAG WARNING FOR THE PALMER
    DIVIDE AREA UNTIL 7 PM MDT TODAY...FIRE WEATHER ZONES
    241..246..AND 247.
  WINTER STORM WARNING THROUGH SUNDAY FOR MOUNTAINS ABOVE 9000
    FEET...ZONES 31..33..34.
  SNOW AND BLOWING SNOW ADVISORY LATE TONIGHT AND SUNDAY FOR EASTERN
   ELBERT AND WESTERN DOUGLAS COUNTIES ABOVE 6000 FEET...ZONE 41.
&&

GIMMESTAD/RJK
Hazardous weather outlook, Oct 20, 11:01 AM MDT, 5 hours 13 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1101 AM MDT SAT OCT 20 2007

COZ030>051-211200-
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-
1101 AM MDT SAT OCT 20 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

...RED FLAG WARNING FOR THE PALMER DIVIDE AREA TODAY...
...WINTER STORM WATCH TONIGHT AND SUNDAY FOR THE MOUNTAINS...

.DAY ONE...TODAY AND TONIGHT

SOUTHWEST WINDS WILL INCREASE TO 15 TO 30 MPH IN AREAS ALONG THE
FOOTHILLS AND SOUTH OF INTERSTATE 70 THIS AFTERNOON...WITH GUSTS AS
HIGH AS 40 MPH. THE GUSTY WINDS WILL COMBINE WITH VERY LOW
HUMIDITIES TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS OVER
DOUGLAS...ELBERT...AND LINCOLN COUNTIES.

SNOW WILL BECOME WIDESPREAD IN THE MOUNTAINS BY THIS EVENING AND MAY
BE HEAVY AT TIMES THROUGH TONIGHT.  ON THE PLAINS...RAIN SHOWERS
WILL DEVELOP THIS EVENING AND THEN MIX WITH AND CHANGE TO SNOW
DURING THE LATE NIGHT HOURS.  SNOW ACCUMULATIONS TONIGHT ARE
EXPECTED TO BE AN INCH OR LESS ON THE PLAINS...BUT BETWEEN 3 AND 8
INCHES IN THE MOUNTAINS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SNOW WILL CONTINUE IN THE MOUNTAINS AND FOOTHILLS ON SUNDAY WITH
RAIN AND SNOW OVER NORTHEAST COLORADO.  ADDITIONAL ACCUMULATIONS IN
THE MOUNTAINS AND FOOTHILLS WILL RANGE FROM 2 TO 5 INCHES.  OVER
NORTHEAST COLORADO SNOW AMOUNTS WILL RANGE FROM 0 TO 2 INCHES WITH
UP TO 5 INCHES POSSIBLE NEAR THE FOOTHILLS AND OVER THE PALMER
DIVIDE.  PRECIPITATION WILL END BY SUNDAY EVENING AS A STORM SYSTEM
MOVES EAST INTO THE CENTRAL PLAINS.

FOR MUCH OF NEXT WEEK...THE WEATHER WILL BE DRY WITH TEMPERATURES
WARMING TO ABOVE SEASONAL NORMALS BY MID WEEK.

.SPOTTER INFORMATION STATEMENT...

SNOWFALL REPORTS FROM SPOTTERS WILL BE APPRECIATED.

GIMMESTAD/RJK

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 20, 4:50 AM MDTRed Flag WarningBOUArapahoe, Douglas, Elbert, Lincoln14 hr
Oct 20, 4:14 PM MDTSnow and Blowing Snow AdvisoryBOUArapahoe, Douglas, Elbert7 hr

Nearby

Winter Storm Warnings in Colorado, 2007Every winter storm warning in 2007

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.