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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
825 PM MDT Tuesday may 26 2015

issued at 825 PM MDT Tuesday may 26 2015

An area of showers and thunderstorms extend from Denver south to
the Colorado-New Mexico border. This convection is slowly moving
east and is expected to linger through the evening hours and
dissipate after midnight as the airmass stabilizes. Over the
mountains...radar is showing a few showers and storms. Most of
these have been weakening and expect them to end by midnight. Will
make some adjustment to probability of precipitation to reflect the current trends.


Short term...(this evening through wednesday)
issued at 157 PM MDT Tuesday may 26 2015

12z models depiction of convection mainly over the higher terrain
this afternoon has developed. We are seeing a few storms with
small hail and locally heavy rain...but with convective available potential energy of 250 or less
severe weather is not expected. There is some indication of
convection blooming over the Palmer Divide this evening and
lingering...and slowly diminishing elsewhere. Have blended with
the Pueblo office to show some lingering storms this evening.

Later tonight and Thursday morning there is a concept of
thunderstorms lingering in Kansas then slowly moving north...this
favored by plains offices...and have introduced isolated midday
storms on Thursday. Thursday looks interesting...with convection
developing from both sides of the County Warning Area. Very large convective available potential energy over 5000
are forecast in Kansas while eastern Colorado will see some convective available potential energy
over 1000. Storm Prediction Center shows a band of marginal risk across northeast
Colorado...which looks reasonable.

Long term...(wednesday night through tuesday)
issued at 157 PM MDT Tuesday may 26 2015

The flow aloft will remain southwesterly on Thursday with the next
system over the northern rockies. Convective available potential energy on Thursday afternoon
500-1000 at excess of 1500 j/kg east of a Sterling to
Akron line. Some of the storms could be severe with large hail
and wind gusts in excess of 60 miles per hour. Weak middle and upper qg ascent
will develop Thursday evening with the trough axis over western
WY/co. The trough axis slowly shift across northern Colorado late
Thursday night through Friday evening. A cold front associated
with the trough will push into the Front Range and Palmer Divide
by 18z with shallow upslope developing in the afternoon. Better
shower vs thunderstorm coverage. Forecast convective available potential energy of 500-700 j/kg Friday
afternoon. Best shear and instability along and south of the
Palmer Divide...south and southeast of Denver. The air mass will become
increasingly stable over the plains as surface high pressure
builds over the region. Some lingering showers Saturday morning.
Southeasterly surface winds on Saturday with best chance of showers/thunderstorms in
and near the foothills and Palmer Divide. Overall less
showers/thunderstorms coverage with ridging aloft. Sunday through
Tuesday...drier and warmer. Better chance of storms may occur


Aviation...(for the tafs through 06z Wednesday evening)
issued at 825 PM MDT Tuesday may 26 2015

Threat for thunderstorms in the Denver area will end around 03z.
Ceilings will remain above 6000 feet tonight and Wednesday. Winds
will be southerly through Wednesday. There will be another chance
for thunderstorms Wednesday afternoon after 21z.


issued at 157 PM MDT Tuesday may 26 2015

Several gages in Weld County and western Morgan County remain in
minor flood stage and are expected to remain there through
Wednesday. Scattered thunderstorms are expected today over the
higher terrain with isolated thunderstorms over the lower
elevations. Flash flood threat will be low as storms should be
moving at 10-15kt and instability not all that strong.

Scattered thunderstorms will develop again Wednesday afternoon
especially over the higher terrain and out over the northeast
plains. Storms will gain move at 10 to 15 miles per hour...with a little
greater instability...some locally heavy rain will be
possible...but flash flooding is unlikely.

Another system with upslope flow associated with it will bring a
chance for heavier rain/thunderstorms Friday into Friday night.


Bou watches/warnings/advisories...


short term...rtg
long term...Cooper

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