Area Forecast Discussion Issued by NWS Cheyenne, WY
000
FXUS65 KCYS 222133
AFDCYS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
333 PM MDT WED MAY 22 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 233 PM MDT WED MAY 22 2013
A FEW SHOWERS HAVE DEVELOPED THIS AFTERNOON ACROSS ALBANY AND
CARBON COUNTIES. ISOLATED SHOWER ACTIVITY WILL CONTINUE INTO EARLY
THIS EVENING BEFORE DYING OFF. SHOWERS WILL TRY TO PUSH EASTWARD
AND COULD REACH THE NEBRASKA BORDER BY THIS EVENING...BUT THAT MAY
BE PUSHING THE EASTERN EXTENT OF ANY ACTIVITY AS A LOW LEVEL
INVERSION WILL BE STRENGTHENING THIS EVENING AS COOL MOIST LOW LEVEL
AIR ADVECTS WESTWARD. SHOWER ACTIVITY COULD BE ACCOMPANIED BY A FEW
WEAK THUNDERSTORMS...BUT THOSE WILL BE FEW AND FAR BETWEEN. SEVERE
THUNDERSTORMS NOT EXPECTED BUT COULD SEE A FEW STRONGER WIND GUSTS
GIVEN 30 TO 40 DEGREE SURFACE DEW POINT DEPRESSIONS. THERE IS A
VERY SMALL CHANCE FOR ELEVATED SHOWERS TO SPREAD EAST ACROSS THE
PANHANDLE THIS EVENING IN ASSOCIATION WITH AN ELEVATED WARM FRONT.
NOT A LOT OF MOISTURE TO WORK WITH SO KEPT POPS BELOW MENTION IN
THE FORECAST BUT SOMETHING TO KEEP AN EYE ON THIS EVENING.
STRATUS DECK HAS HELD FIRM ALL DAY AT CHADRON AND ALLIANCE. THE
STRATUS WILL WORK ITS WAY WEST THIS EVENING...BANKING UP ALONG THE
LARAMIE RANGE. SOME OF THE LOW CLOUDS MAY SPILL INTO THE LARAMIE
VALLEY. FOG WILL BE POSSIBLE ACROSS THE NEBRASKA PANHANDLE AND
PORTIONS OF SOUTHEAST WYOMING...ESPECIALLY ALONG THE LARAMIE RANGE
WHERE LOCALLY DENSE FOG MAY FORM TONIGHT. SOUTHEAST WINDS WILL
RATCHET UPWARD TONIGHT WITH SOME OF THE STRONGEST WINDS EAST OF THE
LARAMIE RANGE. COULD EASILY SEE SOME GUSTS OVER 40 MPH TONIGHT
SUCH AS AROUND DOUGLAS.
WITH THE STRATUS DECK HOLDING FIRM THURSDAY UNDER SOUTHEAST
FLOW...TEMPERATURES WILL STRUGGLE TO RISE ANYWHERE EAST OF THE
LARAMIE RANGE...WHILE MOSTLY SUNNY AND WARM TEMPERATURES WILL BE
FOUND IN THE WEST UNDER SOUTHWEST FLOW. CUT BACK ON CHANCES OF
THUNDERSTORMS EAST OF THE LARAMIE RANGE WITH ISOLATED SHOWERS AND
THUNDERSTORMS WEST. CHANCES FOR THUNDERSTORMS ALONG THE LARAMIE
RANGE ARE DIFFICULT TO HANDICAP...DEPENDING ON WHETHER OR NOT LOW
CLOUDS MIX OUT. CERTAINLY A CONVERGENCE ZONE WITH SOUTHWEST WINDS
MEETING SOUTHEAST WINDS...SO SHOULD CAP WEAKEN...A FEW STORMS
WOULD BE POSSIBLE. NOT EXPECTING SEVERE THUNDERSTORMS...BUT WITH
CAPE AND SHEAR WOULD BE SUPPORTIVE OF A FEW STRONGER
THUNDERSTORMS.
STATUS SHOULD STAY LOCKED IN OVER THE AREA INTO THURSDAY
EVENING...BUT THE MODELS ARE BRINGING IN A STRONG PUNCH OF DRY
SOUTHWEST FLOW ALOFT THURSDAY NIGHT AND FRIDAY. STRATUS SHOULD
ERODE FROM WEST TO EAST DURING THIS TIME. THIS WILL MEAN MUCH
WARMER TEMPERATURES FRIDAY FOR PLACES SUCH AS CHEYENNE AND
DOUGLAS. THE MAIN QUESTION IS HOW FAR EAST WILL THE DRY AIR MAKE
IT. A LARGE TEMPERATURE DIFFERENCE CAN BE EXPECTED OVER A SHORT
DISTANCE COME THURSDAY AFTERNOON...BUT WHERE THAT LINE SETS UP IS
THE MAIN QUESTION. CHANCES FOR THUNDERSTORMS WILL EXIST ALONG AND
EAST OF THE DRY LINE FRIDAY AFTERNOON. SHEAR AND CAPE PROFILES
CONDUCIVE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL
WITH TORNADOES NOT OUT OF THE QUESTION. FOR FRIDAY EVENING...THE
DRY LINE IS EXPECTED TO RETREAT WESTWARD. STORMS VERY WELL MAY
FIRE ALONG THE RETREATING DRY LINE.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 310 PM MDT WED MAY 22 2013
WARMER AND MAINLY DRY CONDITIONS EXPECTED SATURDAY IN SWLY FLOW
WITH SFC BOUNDARY EXPECTED TO BE NORTHEAST OF THE CWA...THOUGH NOT
FAR. PATTERN THEN REMAINS QUITE SIMILAR SUNDAY THROUGH WEDNESDAY
WITH SW FLOW ALOFT OVER THE CWA AHEAD OF AN UPPER TROF THAT WILL
HOLD OVER THE PACIFIC NW. PERIODIC UPPER SHORTWAVE WILL PASS
ACROSS THE REGION AND BRING SOME AFTERNOON AND EVENING CONVECTION
BUT HARD TO SAY WHICH DAYS WILL BE BEST FOR THIS. RIGHT NOW MONDAY
AND TUESDAY LOOKING SOMEWHAT BETTER. TEMPERATURES WILL REMAIN WARM
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 1125 AM MDT WED MAY 22 2013
LOW CLOUDS GRADUALLY BREAKING UP FM KCDR TO KAIA LATE THIS MORNING
AND SHOULD CONTINUE TO BREAK UP TO VFR EARLY THIS AFTERNOON. A FEW
SHOWERS OR TSTMS THIS AFTERNOON INTO THIS EVENING MAINLY AROUND THE
SE WY MTNS. MOIST SOUTHEAST WINDS TONIGHT SHOULD CAUSE LOW CLOUDS
WITH IFR CIGS TO REDEVELOP BETWEEN 06-09Z OVER THE PLAINS.
&&
.FIRE WEATHER...
ISSUED AT 233 PM MDT WED MAY 22 2013
LOW CLOUDS AND FOG TO SPREAD ACROSS THE NEBRASKA PANHANDLE AND
SOUTHEAST WYOMING EAST ALONG AND EAST OF THE LARAMIE RANGE TONIGHT.
WHILE THE FOG WILL BURN OFF THURSDAY BUT LOW CLOUDS AND COOL DAMP
CONDITIONS WILL PERSIST. WEST OF THE LARAMIE RANGE IT WILL BE
DRY AND WARM UNDER SOUTHWEST FLOW ALOFT. FOR FRIDAY...DRY CONDITIONS
ARE EXPECTED TO SHIFT EAST ACROSS THE REMAINDER OF WYOMING ALONG
WITH MUCH WARMER TEMPERATURES. THUNDERSTORMS ARE POSSIBLE OVER THE
NEBRASKA PANHANDLE FRIDAY AFTERNOON AND EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...LIEBL
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...LIEBL