Area forecast discussion
National Weather Service Cheyenne Wyoming
1128 PM MDT Monday may 20 2013
Update...
issued at 904 PM MDT Monday may 20 2013
Allowed the Wind Advisory to expire across western Nebraska this
evening as winds are slowly subsiding from Sidney northward
towards Chadron. Still expect windy conditions to continue tonight
across the High Plains...but not expecting many gusts higher than
40 miles per hour. Lowered pop along and south of i80 with shower activity
dissipating. Rain showers will be mainly confined to Niobrara
County eastward into the northern Panhandle of Nebraska through
Tuesday morning. The storm responsible for this rain...windy...and
mountain snow will then begin to push east towards the eastern
Dakotas and Minnesota on Tuesday.
&&
Short term...(this evening through Wednesday night)
issued at 330 PM MDT Monday may 20 2013
Vorticity lobe shifting southward out of South Dakota bringing a shot
of light rain to northern portions of the forecast
area...otherwise showers will wind down across the area this
evening. Dry northwest flow and minimal instability will allow
most shower activity to end this evening.
Northwest winds have been strong much of the day...especially
along and east of the Laramie range. Sustained winds of 30 to 40
miles per hour with gusts generally 45 to 55 miles per hour. A few higher gusts have
been reported but those have been few and far between. Winds have
started to slowly decrease and will continue to due so this
evening. The Wind Advisory for the Nebraska Panhandle remains in
effect until 9 PM this evening.
Upper ridge to build into the area Tuesday with drier conditions
and warmer temperatures. A few light rain showers are possible
over the northern County Warning Area but that should be about all. Will start to
see some instability return Wednesday which could allow for a few
afternoon thunderstorms mainly over the mountains and adjacent
areas.
Long term...(thursday through monday)
issued at 330 PM MDT Monday may 20 2013
Weather over the County Warning Area will be affected mainly by a couple of upper
lows over the Pacific northwest which will put the area under southwesterly flow
aloft. Periods of mainly late day showers and thunderstorms are
expected as weak impulses round the base of these lows and eject
northeast across the region. Best chances will be over the
Panhandle where activity should be aided by a surface boundary which
will meander in that area. Impulses will be hard to time but best
chances look to be Thursday and Friday and Sunday. Temperatures
will be seasonal through the period.
&&
Aviation...(for the 06z tafs through 06z Tuesday evening)
issued at 1118 PM MDT Monday may 20 2013
Latest radar loop was showing light showers continuing to affect
the cdr taf site. Ceilings in western South Dakota were mainly in the MVFR
category in the rain bands. Would not surprised if the ceilings
drop into the MVFR category during the next hour or two...but they
may fluctuate between VFR and MVFR during the course of the night.
After daybreak...the ceilings should climb to the VFR
category. Elsewhere...ceilings should remain VFR through the next
24 hours. Gusty northwest winds can be expected once again 15z-00z
especially across the Panhandle taf sites...due to good mixing.
Cox
&&
Fire weather...
issued at 330 PM MDT Monday may 20 2013
Gusty winds will continue across much of southeast Wyoming and
the Nebraska Panhandle through early this evening and then
winds will decrease through the overnight hours. Rain showers
will decrease in intensity and coverage this evening with only
a few light rain showers. A few light rain showers possible
over east central Wyoming and the northern Nebraska Panhandle
Tuesday...otherwise dry across the forecast area. Chances for
thunderstorms Wednesday and into the weekend with the main
chances along and east of the Laramie range and into the snowy
and Sierra Madre ranges.
&&
Cys watches/warnings/advisories...
Wyoming...none.
NE...none.
&&
$$
Update...tjt
short term...liebl
long term...re
aviation...Cox
fire weather...liebl
