Alert archive / Colorado / Winter Storm Watches in 2016

Winter Storm Watch 10, NWS Denver/Boulder, CO

April 28, 2016Arapahoe County, Douglas County, Elbert County, Colorado

NWS Denver/Boulder, CO issued this winter storm watch at Apr 28, 2016, 4:26 AM MDT for Arapahoe County, Douglas County, Elbert County, Colorado. It took effect at Apr 28, 2016, 6:00 PM MDT. It was in force for .

The area

The counties it named.

The facts

Issued
Apr 28, 2016, 4:26 AM MDT (10:26 UTC)
In effect from
Apr 28, 2016, 6:00 PM MDT
Expired
Apr 28, 2016, 12:43 PM MDT
In force
Issued by
NWS Denver/Boulder, CO

Counties Arapahoe County, CO, Douglas County, CO, Elbert County, CO

The radar

The Denver radar (KFTG), 41 km from the middle of the area, began a volume at 10:28 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, 10.4 hours before the alert went out and 117 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 00:00Z on 2016-04-28Temperature 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 00:00Z on 2016-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
1796 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
235 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 winter storm watch 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 watch went out at Apr 27, 4:00 PM MDT, 12 hours 26 minutes earlier.

Area forecast discussion, Apr 27, 4:00 PM MDT, 12 hours 26 minutes before
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Hazardous weather outlook, Apr 27, 11:50 AM MDT, 16 hours 36 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1150 AM MDT WED APR 27 2016

COZ030>051-281800-
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-
1150 AM MDT WED APR 27 2016

...WINTER STORM WATCH IN EFFECT FOR THE FRONT RANGE MOUNTAINS AND
FOOTHILLS FROM EARLY THURSDAY EVENING TO LATE FRIDAY EVENING...

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED LIGHT SNOW SHOWERS WILL CONTINUE OVER HIGHER ELEVATIONS
OF THE FRONT RANGE MOUNTAINS FOR THE REMAINDER OF TODAY...WITH ANY
NEW ACCUMULATIONS GENERALLY UNDER 2 INCHES AND MAINLY ON NORTHWEST
FACING SLOPES. ON THE PLAINS...GUSTY NORTHWEST WINDS WILL CONTINUE
TODAY WITH POSSIBLE GUSTS TO AROUND 40 MPH IN AREAS MAINLY EAST
OF INTERSTATE 25. IN ADDITION...EXPECT A FEW LIGHT RAIN SHOWERS TO
DRIFT OFF THE FRONT RANGE THIS AFTERNOON...WITH RAIN AMOUNTS NO
MORE THAN A COUPLE HUNDREDTHS OF AN INCH. TONIGHT...SNOW SHOWERS
WILL BE ON THE INCREASE OVER MOUNTAIN AREAS GENERALLY SOUTH OF
INTERSTATE 70 WHERE A FEW INCHES OF SNOW MAY FALL BY MORNING. ON
THE PLAINS...LOOK FOR PATCHY FOG TO FORM LATE TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A STORM SYSTEM WILL DEVELOP INTO THE FOUR CORNERS REGION THURSDAY
SPREADING PRECIPITATION ACROSS THE OUTLOOK AREA DURING THE DAY.
THIS PRECIPITATION WILL CONTINUE THROUGH AT LEAST FRIDAY EVENING
AS THE STORM TRAVERSES COLORADO. SIGNIFICANT SNOW ACCUMULATIONS
WILL LIKELY OCCUR IN THE HIGH COUNTRY. IT IS NOT CERTAIN AT THIS
TIME WHETHER TEMPERATURES AT LOWER ELEVATIONS WILL BE COLD ENOUGH
TO PRODUCE SNOW BUT MIXED PRECIPITATION IS NOT OUT OF THE
QUESTION ACROSS THE PLAINS AND URBAN CORRIDOR.

THE STORM SHOULD EXIT THE STATE SATURDAY...LOWERING THE CHANCES OF
PRECIPITATION AT THAT TIME BUT ANOTHER STORM MAY DEVELOP SIMILARLY
TO BRING ANOTHER ROUND OF RAIN AND SNOW TO THE OUTLOOK AREA EARLY
NEXT WEEK.

TEMPERATURES WILL BE WELL BELOW NORMAL THROUGHOUT THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.

BAKER/ET

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 28, 4:26 AM MDTWinter Storm WarningBOUBoulder, Clear Creek, Douglas, Gilpin, Grand, Jackson and 4 more36 hr
Apr 28, 12:43 PM MDTWinter Weather AdvisoryBOUArapahoe, Boulder, Clear Creek, Douglas, Elbert, Gilpin and 6 more32 hr

Nearby

Winter Storm Watches in Colorado, 2016Every winter storm watch in 2016

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.