Severe Thunderstorm Warning 149, NWS Denver/Boulder, CO

Area Forecast Discussion
National Weather Service Denver/Boulder CO
935 PM MDT TUE JUL 12 2016

.UPDATE...
Issued at 935 PM MDT Tue Jul 12 2016

Storms have generated on the back edge of outflow. As a result,
see isolated storm development as far west as the eastern portions
of the Denver Metro area so far. Will adjust thunderstorm chances
accordingly and also delay their departure overnight.

UPDATE Issued at 801 PM MDT Tue Jul 12 2016

As expected...a few weak thunderstorms have developed just north
of the palmer divide and are drifting east. there is an apparent
weak upper trough seen on water vapor imagery that is moving
through central wyoming and northwest colorado...as a result these
storms should spread into kansas by 11pm. These storms may produce
some small hail.

Overall the forecast is in good shape...no changes.

&&

.SHORT TERM...(This evening through Wednesday)
Issued at 337 PM MDT Tue Jul 12 2016

Warm temperatures and low humidities have returned this afternoon,
especially in the mountain areas. Moderate westerly flow aloft has
mixed down to the surface in the mountains with the warm
temperatures. On the plains...showers have failed to materialize
up to this point, but the HRRR shows a few showers over the Palmer
Divide in the next few hours. This will be the only areas of
weather this evening. For tomorrow...more of the same weather is
expected as westerly flow aloft continues. Temperatures are
expected to be a few degrees warmer under the persistent warm
ridging over the region. Medium range models do not generate any
shower activity tomorrow afternoon, but we will wait to see if the
shorter range models generate showers tomorrow morning.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 337 PM MDT Tue Jul 12 2016

The strong Westerly flow aloft will shift a bit more Northwesterly
for Thursday and Friday. This will open the door for some cooler
temperatures and weak surges moving into  Northeast Colorado.
Moisture levels will also increase across the plains leading to a
better chance for showers and thunderstorms by late Thursday
afternoon and again for Friday. There are some differences showing
up in model solutions with the NAM being the cooler and wetter
model while GFS solution is drier and warmer. At this time will go
more in the middle road and see how things evolve as the week
goes along. If in fact the NAM is correct may even see severe
storms on the plains given higher dewpoints and CAPE values
upwards of 2000j/kg on the plains and modest shear.

The flow again shifts back more Southwest over the weekend as the
broad high pressure builds back over the Southern High plains.
Drier and warmer temperatures return under the SW flow. Model
trends by early next week indicate the High pressure aloft will
rebuild further North into the Central portion of the country
which may begin to steer moisture back into Colorado from the
Southwest.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 935 PM MDT Tue Jul 12 2016

Thunderstorm in the vicinity of KDEN that developed along outflow
boundary will likely move off to the east toward 05Z. Otherwise
VFR conditions and winds transitioning to normal drainage patterns
expected.

&&

.FIRE WEATHER...
Issued at 337 PM MDT Tue Jul 12 2016

Extremely low relative humidities are being observed in North and
Middle Park along with breezy conditions. Will let the Red Flag
Warning continue through expiration at 8 PM.

For Wednesday...much the same conditions are expected as moderate
zonal flow aloft continues with temperatures maybe a degree or
two warmer. Fire behavior this afternoon has been more limited
than yesterday, but may pick up again tomorrow. Will issue a Fire
Weather Watch for North, Middle and South Parks, along with the
northern Front Range Foothills.

&&

.BOU Watches/Warnings/Advisories...
Fire Weather Watch from Wednesday morning through Wednesday
evening for COZ211-213>215-217.

&&

UPDATE...Barjenbruch
SHORT TERM...Dankers
LONG TERM...Entrekin
AVIATION...Barjenbruch
FIRE WEATHER...Dankers

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1113 AM MDT TUE JUL 12 2016

COZ030>051-131715-
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-
1113 AM MDT TUE JUL 12 2016

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

.DAY ONE...TODAY AND TONIGHT

WESTERLY FLOW ALOFT WILL AGAIN BRING GUSTY WEST WINDS AND LOW
RELATIVE HUMIDITIES TO THE NORTHERN MOUNTAINS TODAY. WIND GUSTS
OF 25 TO 35 MPH AND RELATIVE HUMIDITIES IN THE TEENS WILL KEEP
THE FIRE DANGER ELEVATED.

THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS LATE THIS
AFTERNOON AND EVENING OVER THE PALMER DIVIDE. THE STORMS WILL BE
CAPABLE OF PRODUCING BRIEF HEAVY RAIN, HAIL UP TO ONE INCH IN
DIAMETER, AND GUSTY OUTFLOW WINDS. THE REST OF THE NORTHEAST
COLORADO PLAINS SHOULD REMAIN DRY.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

MAINLY DRY CONDITIONS WILL PREVAIL THROUGH THURSDAY MORNING.
THERE WILL BE A BETTER CHANCE OF LATE DAY SHOWERS AND
THUNDERSTORMS THURSDAY AND FRIDAY...ESPECIALLY ON THE NORTHEAST
PLAINS OF COLORADO. THERE COULD BE SEVERE STORMS ON THE PLAINS ON
BOTH THURSDAY AND FRIDAY.  TEMPERATURES WILL MOVE BACK INTO THE
MID 90S ON WEDNESDAY THEN FALL INTO THE 80S FOR THURSDAY AND
FRIDAY FROM A SET OF DISTURBANCES. A WARM-UP WILL OCCUR FOR THE
LATTER HALF OF THE WEEK.

ELEVATED FIRE DANGER WILL CONTINUE THROUGH THE MIDDLE OF THE WEEK
DUE TO DRY WEATHER AND WARM TEMPERATURES.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.