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Area forecast discussion 
National Weather Service Cheyenne Wyoming
1054 PM MDT Thursday Jul 24 2014

issued at 848 PM MDT Thursday Jul 24 2014

The early evening upper air analysis showed a shortwave trough
lifting quickly northeast across Montana and the Dakotas. Trailing
weak vorticity lobe provided lift for afternoon convection over
much of the County Warning Area. This feature has moved east into central NE.
Drying aloft was spreading into western and central Wyoming...and
will push into southeast Wyoming and western NE Panhandle overnight.
A weak cool front will slide southeast through the County Warning Area. Moderate
southwest winds will decrease and shift to the northwest after
frontal passage. Radar showed a weakening tstorm south of Rawlins.
Expect dry conditions after middle evening with mostly clear skies.


Short term...(this afternoon through saturday)
issued at 249 PM MDT Thursday Jul 24 2014

Isolated showers and thunderstorms will move across the area the
rest of the afternoon and early evening before dissipating. Severe
thunderstorms are not expected. Like usual gusty winds and brief
heavy rain will be possible with some showers and thunderstorms.

A cold front will push across the plains tonight...ushering in
slightly cooler air. This will be a shallow push of cool air with
the airmass quickly modifying by Friday afternoon. Temperatures
Friday will again climb into the 90s over much of the forecast
area...but not looking for triple digit heat like is occurring in
the Panhandle today. Chances for thunderstorms are on the low side
Friday but there will be a few thunderstorms to develop over the
mountains which may work east into the plains. Main chances for
storms should be over southern portions of the forecast area.
Severe thunderstorms not expected.

Another cold front will push across the area Friday night. Again
not a lot of cold air to work with but most of the area should be
about 5 degrees cooler Saturday with highs in the middle 80s to lower
90s. Saturday should be dry with only a small chance for
thunderstorms over the mountains near the Colorado border but most
likely monsoon moisture will stay south of the area.

Long term...(saturday night through wednesday)
issued at 249 PM MDT Thursday Jul 24 2014

Northwesterly flow will be established over the County Warning Area this period
with an upper ridge situated to the west and a large upper trough
over eastern North America. This pattern will allow for cooler air
to drop out of Canada across the plains with the County Warning Area on the
western side of the cooler air mass. A cool front will pass
across Saturday night with a surface high then setting up over the
northern and Central Plains into the middle part of next week.
Monsoonal moisture will be suppressed to the south through Monday
with mainly dry weather across the County Warning Area. Some return of moisture
should happen Tuesday while an upper shortwave drops southeast across the
region. This should provide the best chance for precipitation across much
of the County Warning Area Tuesday into Tuesday night before a drier regime
returns Wednesday.


Aviation...(for the 06z tafs through 06z Friday evening)
issued at 1050 PM MDT Thursday Jul 24 2014

VFR conditions through the taf period. A weak front will pass
across the plains overnight with northwest winds (generally less
than 15 kts) behind it. Midlvl clouds will pass near the Colorado
border from time to time through sunrise. Isolated showers and thunderstorms
will develop during the afternoon on Friday.


Fire weather...
issued at 249 PM MDT Thursday Jul 24 2014

Red flag warning for zone 301 will expire this evening as winds
begin to subside and humidity values slowly recover. Critical to
near critical conditions will return to zone 301 Friday due to
gusty winds and humidity values in the teens. Zones 304 and 306
will also see similar conditions. Slightly cooler for this weekend
along with less winds so not expecting critical fire conditions
east of the Laramie range...but could see breezy winds west of the
Laramie range along with low humidity values.


Cys watches/warnings/advisories...


short term...small
fire weather...small

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