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fxus65 kpub 260959 

Area forecast discussion
National Weather Service Pueblo Colorado
359 am MDT Wed Jul 26 2017

Short term...(today and tonight)
issued at 355 am MDT Wed Jul 26 2017

... Rain...and possible flash flooding ahead...

Total precipitable water (tpw) values are running 150 to 170% of
average over southern Colorado. These are the highest values i've
seen in the past 4 nights. Dewpoints are equally impressive with
widespread 60s across the plains and even 50s in the high valleys at
Alamosa and Salida. It's sticky out there. The monsoon is well
entrenched and the moisture is deep. Models are forecasting plenty
of cape for storms today. High res models show a lot of convection
firing over southern Colorado in the afternoon, congealing into an
mesoscale convective system and continuing east to southeast across the plains through the
evening and overnight hours. Big quantitative precipitation forecast bull's-eyes are being forecast
by all models in varying locations. Can't be exactly sure where the
greatest amounts will fall. But the point is...somebody is going to
get a lot of rain. Considering our burn scar sensitivity to heavy
rain and the slow moving mesoscale convective system expected to move across our plains
tonight, will go with a Flash Flood Watch for the eastern mountains
and plains from 21z this afternoon to 09z Thursday morning.
Southeast Colorado seems to be the target for the heaviest rain this
go around. So, while we will have a Flash Flood Watch out,
surrounding offices likely will not, at least at this time. This is
per collaboration with surrounding forecast offices early this

Additionally, there will be enough cape out there today (maybe 1500
j/kg) and enough shear for the possibility of a few severe storms
across the plains today. The air aloft is pretty warm due to the
monsoon nature of the airmass but the high Cape May compensate
enough to produce a few 1 inch hailers and 60+ mph winds. An active
day ahead!

Long term...(thursday through tuesday)
issued at 355 am MDT Wed Jul 26 2017

Upcoming locally heavy rainfall will bring the potential for flash

Upper ridge will be quasi-stationary across the southwest and south
central US, with the moisture rich monsoon plume over the central
rockies through the rest of this week. This means widespread daily
showers and storms, first developing across the higher terrain and
then spreading into the adjacent high valleys and eastern plains.
Models have rain chances continuing into and through the overnight
as well. With the relatively weak flow aloft, and probable
development of mcs's, areas of heavy rain totals and potential flash
flooding will occur, especially across urban areas and burn scars.
There may be a few marginally severe storms during this time period,
and temperatures will be below seasonal norms, with abundant cloud

Through the weekend and early next week, trough across the eastern
US will push the upper ridge farther west. Scattered afternoon and
evening showers and storms will be the rule, and be more
concentrated across the higher terrain and adjacent locations.
Storms would be enhanced, at times, with difficult to time
shortwaves rippling through the flow. There will still be the
potential for locally heavy rain totals and flash flooding, again
primarily across urban areas and burn scars. Temperatures will
remain below seasonal norms.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 355 am MDT Wed Jul 26 2017

Widespread showers and thunderstorms will develop over the mountains
and spread east across the plains through the evening and overnight
hours tonight. Initial convection will develop over the mountains
between 11 am and 1 PM, becoming scattered by 3 PM and then becoming
widespread across the plains after that through the evening. The
western mountains and valleys will see less activity today than
locations farther east. Generally VFR through 11 am but then
conditions deteriorating through the afternoon and evening to
scattered then widespread MVFR, IFR and LIFR conditions, especially
along and east of the mountains. All 3 terminals, kals, kcos,
kpub, will see a chance of storms today, generally beginning
around 20z. Kals likely has the least chance of storms today while
kcos and kpub have much better chances. A stormy monsoon
afternoon and evening ahead.


Pub watches/warnings/advisories...
Flash Flood Watch from 3 PM MDT this afternoon through late
tonight for coz072>089-093>099.


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