Alert archive / Colorado / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 184, NWS Denver/Boulder, CO

July 7, 2014Washington County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 7, 2014, 11:22 PM MDT for Washington County, Colorado. It was in force for 20 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 7, 2014, 11:22 PM MDT (05:22 UTC)
Expired: Jul 7, 2014, 11:42 PM MDT
In force: 20 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Washington County, CO

The radar

The Denver radar (KFTG), 117 km from the middle of the area, began a volume at 05:22 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 (KDEN), launched 00:00Z, 5.4 hours before the alert went out and 11 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 266 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 3850 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -28 m²/s²
0-3 km storm-relative helicity: 3 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Jul 7, 9:49 PM MDT, 1 hour 33 minutes earlier.

Area forecast discussion, Jul 7, 9:49 PM MDT, 1 hour 33 minutes before

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Hazardous weather outlook, Jul 7, 11:23 AM MDT, 11 hours 59 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1123 AM MDT MON JUL 7 2014

COZ030>051-081730-
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-
1123 AM MDT MON JUL 7 2014

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

.DAY ONE...TODAY AND TONIGHT

ANOTHER HOT DAY IN STORE FOR THE OUTLOOK AREA WITH AFTERNOON
READINGS NEARING RECORD LEVELS FOR PARTS OF THE PLAINS. THEN A
SHIFT TO GUSTY NORTHEAST WINDS LATE THIS AFTERNOON WILL SIGNAL THE
START OF A ONE DAY COOL DOWN FOLLOWING THE PASSAGE OF A STRONG
COLD FRONT EARLY THIS EVENING. BEHIND THIS FRONT...LOW LEVEL
MOISTURE...INSTABILITY AND UPSLOPE FLOW WILL INCREASE...RESULTING
IN SCATTERED THUNDERSTORMS THIS EVENING. SOME OF THESE STORMS MAY
BECOME STRONG OR BRIEFLY SEVERE WITH HAIL UP TO 1 INCH IN
DIAMETER. THE PLAINS AND I-25 URBAN CORRIDOR ROUGHLY SOUTH OF
U.S. HIGHWAY 34 HAVE THE BEST CHANCE FOR SEEING THIS HAIL. STORMS
ARE EXPECTED TO DIMINISH TOWARDS THE MIDNIGHT HOUR.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

TUESDAY STILL APPEARS TO BE MUCH COOLER ON THE PLAINS BEHIND A
COLD FRONT SCHEDULED TO PUSH SOUTH ACROSS THAT AREA MONDAY
EVENING. THE FLOW BEHIND THIS FRONT WILL USHER IN MORE MOISTURE
INCREASING THE THREAT OF AFTERNOON AND EVENING THUNDERSTORM
ACTIVITY...ESPECIALLY IN THE FOOTHILLS AND ACROSS THE PLAINS. THE
INCREASED MOISTURE WILL ELEVATE THE POSSIBILITY OF LOCALLY HEAVY
RAINS FROM THOSE STORMS THAT DEVELOP.

RELATIVELY NORMAL CONDITIONS WILL LIKELY OCCUR THROUGH THE
REMAINDER OF THE WEEK WITH THE THREAT OF AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS CONTINUING. WITH THE AMOUNT OF MOISTURE
EXPECTED TO BE AROUND...LOCALLY HEAVY RAINS WILL CONTINUE TO BE
POSSIBLE WITH THE STORMS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

BAKER/ET

In the hours before

Local storm report, Jul 7, 8:19 PM MDT, 3 hours 3 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DENVER CO
819 PM MDT MON JUL 07 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0818 PM     HAIL             LOUISVILLE              39.97N 105.14W
07/07/2014  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0809 PM     HAIL             3 SW AGATE              39.44N 103.99W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

0804 PM     HAIL             2 S AGATE               39.44N 103.95W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

&&

JK

Local storm report, Jul 7, 8:40 PM MDT, 2 hours 42 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DENVER CO
840 PM MDT MON JUL 07 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0840 PM     HAIL             ARVADA                  39.82N 105.11W
07/07/2014  M1.00 INCH       JEFFERSON          CO   TRAINED SPOTTER

0839 PM     HAIL             2 NW ARVADA             39.84N 105.13W
07/07/2014  M1.75 INCH       JEFFERSON          CO   TRAINED SPOTTER

0835 PM     TSTM WND GST     ARVADA                  39.82N 105.11W
07/07/2014  E70.00 MPH       JEFFERSON          CO   TRAINED SPOTTER

            FOUR TO SIX INCH DIAMETER TREE BRANCHES BROKEN

0818 PM     HAIL             LOUISVILLE              39.97N 105.14W
07/07/2014  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0815 PM     HAIL             LOUISVILLE              39.97N 105.14W
07/07/2014  M1.25 INCH       BOULDER            CO   TRAINED SPOTTER

0809 PM     HAIL             3 SW AGATE              39.44N 103.99W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

0804 PM     HAIL             2 S AGATE               39.44N 103.95W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

&&

JK

Local storm report, Jul 7, 8:58 PM MDT, 2 hours 24 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DENVER CO
858 PM MDT MON JUL 07 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0842 PM     HAIL             ARVADA                  39.82N 105.11W
07/07/2014  M1.25 INCH       JEFFERSON          CO   TRAINED SPOTTER

            52ND AND WARD

0840 PM     HAIL             ARVADA                  39.82N 105.11W
07/07/2014  M1.00 INCH       JEFFERSON          CO   TRAINED SPOTTER

0840 PM     HAIL             ARVADA                  39.82N 105.11W
07/07/2014  M1.00 INCH       JEFFERSON          CO   TRAINED SPOTTER

            64TH AND WARD...FOUR TO FIVE INCH DIAMETER BRANCHES WERE
            TORN OFF THE TREES FROM THE WIND AND HAIL

0839 PM     HAIL             2 NW ARVADA             39.84N 105.13W
07/07/2014  M1.75 INCH       JEFFERSON          CO   TRAINED SPOTTER

0838 PM     HAIL             ARVADA                  39.82N 105.11W
07/07/2014  E1.25 INCH       JEFFERSON          CO   TRAINED SPOTTER

0835 PM     TSTM WND GST     ARVADA                  39.82N 105.11W
07/07/2014  E70.00 MPH       JEFFERSON          CO   TRAINED SPOTTER

            FOUR TO SIX INCH DIAMETER TREE BRANCHES BROKEN

0818 PM     HAIL             LOUISVILLE              39.97N 105.14W
07/07/2014  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0815 PM     HAIL             LOUISVILLE              39.97N 105.14W
07/07/2014  M1.25 INCH       BOULDER            CO   TRAINED SPOTTER

0809 PM     HAIL             3 SW AGATE              39.44N 103.99W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

0804 PM     HAIL             2 S AGATE               39.44N 103.95W
07/07/2014  M1.00 INCH       ELBERT             CO   TRAINED SPOTTER

&&

JK

Local storm report, Jul 7, 9:38 PM MDT, 1 hour 44 minutes before

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Local storm report, Jul 7, 9:57 PM MDT, 1 hour 25 minutes before

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Local storm report, Jul 7, 10:16 PM MDT, 1 hour 6 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 7, 6:14 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	31 min
Jul 7, 6:58 PM MDT	Areal Flood Advisory	BOU	Larimer	92 min
Jul 7, 7:15 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	45 min
Jul 7, 7:27 PM MDT	Areal Flood Advisory	BOU	Lincoln	2 hr
Jul 7, 7:58 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Larimer	26 min
Jul 7, 8:01 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	44 min
Jul 7, 8:05 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Boulder, Broomfield, Denver, Jefferson	25 min
Jul 7, 8:10 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	23 min
Jul 7, 8:20 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Elbert	40 min
Jul 7, 8:28 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Boulder, Broomfield, Denver, Jefferson	32 min
Jul 7, 9:02 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe	28 min
Jul 7, 9:12 PM MDT	Flash Flood Warning	BOU	Arapahoe, Elbert	3 hr
Jul 7, 9:29 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Washington	31 min
Jul 7, 10:58 PM MDT	Areal Flood Advisory	BOU	Clear Creek, Jefferson, Park	2 hr
Jul 7, 11:40 PM MDT	Areal Flood Advisory	BOU	Jefferson	95 min
Jul 8, 2:31 PM MDT	Special Weather Statement	BOU	Park	29 min
Jul 8, 3:02 PM MDT	Special Weather Statement	BOU	Park	28 min
Jul 8, 4:03 PM MDT	Special Weather Statement	BOU	Park	27 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2014 Every severe thunderstorm warning in 2014

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.