National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KCYS 221126
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
526 AM MDT Sat Jul 22 2017

.SHORT TERM...(Today through Sunday Night)
Issued at 230 AM MDT Sat Jul 22 2017

Quasi-stationary frontal boundary across our southeastern zones
will be the focusing mechanism for isolated showers and
thunderstorms this afternoon and early evening along the I-80
corridor from Cheyenne east to Sidney (a bit greater coverage near
Sidney). Model soundings today indicate skinny CAPEs with a
drying trend in the midlevels. While we do not expect to see
severe storms today, the soundings do suggest a few showers and
storms could be gusty with winds to near 50 mph. For Sunday,
again not a lot of coverage of showers and storms that develop
with mostly isolated development expected across the south Laramie
Range, but with a stronger inverted V subcloud layer model
sounding those isolated cells could produce a bit stronger gusty
winds tomorrow.

.LONG TERM...(Monday through Friday)
Issued at 218 AM MDT Sat Jul 22 2017

Monday...Weak ridging aloft combined with minimal low and mid level
moisture suggests a mostly dry day with perhaps isolated afternoon
thunderstorms from Alliance to Sidney. Warmer day compared to Sunday
per increases in 700 mb temperatures.

Tuesday...A bit cooler than Monday with more cloud cover expected.
Definite increases in low and mid level moisture, thus expect
isolated to scattered afternoon and evening showers and
thunderstorms, most numerous over our western and northeastern
counties.

Wednesday...Despite weak ridging aloft overhead, the presence of
adequate low and mid level moisture will help produce scattered
showers and thunderstorms, most numerous near the mountains. A bit
cooler with more cloud cover and greater areal coverage of showers
and thunderstorms.

Thursday...Considerably less coverage of showers and thunderstorms
with a corresponding decrease in low and mid level moisture.

Friday...Ridging develops moreso aloft. With limited low and mid
level moisture, and warm temperatures aloft, expect isolated
thunderstorms at best, except for scattered coverage over the Snowy
Range where deeper moisture will exist.

&&

.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 524 AM MDT Sat Jul 22 2017

VFR, with isolated thunderstorms near Cheyenne, Sidney and
Alliance from 19Z to 02Z.

&&

.FIRE WEATHER...
Issued at 218 AM MDT Sat Jul 22 2017

Dry but not critically low RH expected for the next few days with
generally light to moderate winds remaining below Red Flag Warning
criteria. Isolated thunderstorms possible in the higher terrain
for the next few days, so a few lightning starts will remain
possible.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&

$$

SHORT TERM...Garmon
LONG TERM...Rubin
AVIATION...RUBIN
FIRE WEATHER...Garmon