Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/13/20

Area Forecast Discussion

National Weather Service Denver/Boulder CO

 841 PM MDT Tue May 12 2020

.UPDATE...
Issued at 829 PM MDT Tue May 12 2020

There is a fair amount of middle and upper cloudiness over and
upstream of the CWA this evening. Will need to keep some
cloudiness in all night. There is still a bit of convective
cloudiness and a few returns on the radars right now, but doubt
any rain is hitting the goring anywhere. Will make a few cosmetic
alterations to the the GFE grids, but nothing significant.
overnight low temperatures will be considerably warmer then this
morning`s reading were.

&&

.SHORT TERM...(This evening through Wednesday)
Issued at 245 PM MDT Tue May 12 2020

Stratus holds tight over the eastern plains, with only very slow
erosion noted east of a Sterling to Limon line this afternoon. We
don`t see much further progression into early evening with a
continuation of moist south/southeast flow. We`ll keep some fog in
the forecast out there through the night. The rest of the
forecast area will see partly cloudy skies this evening with just
some cirrus floating across. We still can`t rule out an isolated
shower/storm south of Denver, but overall the airmass is quite
stable due to some warming aloft and a cooler boundary layer that
was not able to reach convective temps due to the morning stratus
(local AMDAR soundings show the inversion nicely). Temps would
have to hit 78F or so, and we`re at 74F in the warmest spot near
Centennial. With a couple hours of heating yet, can`t rule out an
isolated storm so we`ll keep just a small chance in the forecast
early this evening south of Denver.

On Wednesday, dry and warm southwest flow aloft will be over the
forecast area. That will lead to higher fire danger...see Fire
Weather Discussion section. Temperatures will be warmer with highs
in the upper 70s to lower 80s across all of the plains. Breezy
conditions will develop with the lee trough finally moving off to
the east. That will also take any early morning fog on the eastern
plains out of the picture. Daytime heating and just enough moisture
will bring a slight chance of a showers and storms to the
northern mountains and northern border area late in the day. The
rest of the forecast area will be far too dry to support any
precip chances.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 247 PM MDT Tue May 12 2020

A cold front will slide down Wednesday night, with most shower
activity remaining over the northern third of the forecast.
Showers will be done by midnight, but will have isolated activity
remain over the northern mountains as a jet remains nearby in
Wyoming. High surface pressure moving into the Great Plains will
push in moist air on southeasterly winds for Thursday. This is
combination with another shortwave trough moving in from the Great
Basin and into the the state during the evening, will bring
widespread showers and a slight chance of thunderstorms to the
area Thursday afternoon and into the evening, with showers
remaining after midnight over most of the area.

An upper low over the Pacific Northwest will then drop southeast
and move across the Northern Rockies for Friday, to bring more
instability to the state. Modeled CAPEs of 1000-1800 J/kg are
being shown for the plains, with bulk shear values of 40-60 kts.
This will bring a threat of stronger storms with possible damaging
winds and hail for the afternoon and early evening. With the upper
trough axis not passing overhead until early Saturday morning,
showers and possible storms will continue overnight, slowly
dissipating from west to east.

Even though high pressure aloft will begin to build in from the
west ahead of a large weather pattern change, high surface
pressure behind the system will keep in upslope flow over the
plains Saturday, keeping a chance for showers around for the day.

Sunday through Tuesday will be a much warmer and drier pattern as
larger system slowly approaches the West Coast and allows the
upper ridge to build ahead of it over the state. Southwesterly
flow aloft will bring 700 mb temperatures of near 17 degrees C by
Monday. This would translate into highs near 90 over the urban
corridor.

&&

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 829 PM MDT Tue May 12 2020

Models do show normal drainage wind patterns overnight. There is
will be no ceiling issues at DIA.

&&

.FIRE WEATHER...
Issued at 245 PM MDT Tue May 12 2020

West/southwest flow will strengthen on Wednesday, bringing gusty
winds to the mountains, high valleys, foothills, and nearby
adjacent plains. The driest fuels are located in South Park, and
that`s also where the combination of lowest humidities (10-15%) and
strongest winds can be expected. Therefore, we`ve issued a Red
Flag Warning there. Foothill locations will also see elevated fire
danger, but there has been some recent green-up of grasses and
wind speeds/RH combination look marginal for a Red Flag event.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon to 8 PM MDT Wednesday for COZ214.

&&

$$

UPDATE.........Koopmeiners
SHORT TERM.....Barjenbruch
LONG TERM......Kriederman
AVIATION.......Koopmeiners
FIRE WEATHER...Barjenbruch