Area Forecast Discussion
Issued by NWS Riverton, WY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

000
FXUS65 KRIW 102127
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
327 PM MDT THU APR 10 2014

.SHORT TERM...TONIGHT THROUGH SUNDAY

MILD NW FLOW TO PREVAIL THROUGH FRIDAY NIGHT AHEAD OF OUR WEEKEND
STORM SYSTEM. MID LEVEL TEMPERATURES WILL REBOUND TONIGHT AND FRIDAY
PRODUCING ANOTHER WARM DAY ON FRIDAY. NOT QUITE AS WARM AS WEDNESDAY
BUT STILL WELL ABOVE NORMAL FOR MOST AREAS. WE WILL STILL HAVE TO
DEAL WITH BREEZY TO WINDY PERIODS AND SOME CLOUDINESS FROM TIME TO
TIME BUT OTHERWISE...DECENT EARLY APRIL WEATHER. ALL THAT WILL COME
TO A CRASHING HALT WITH OUR WEEKEND STORM SYSTEM. THIS SYSTEM IS
POISED TO COME ONTO THE BRITISH COLUMBIA COAST SOON AND THEN TURN
SSEWD AND BEGIN STRENGTHENING AND MOVING INTO THE NORTHERN ROCKIES
FRIDAY NIGHT AND SATURDAY. THIS SYSTEM WILL SLOW DOWN SOME AS THE
RIDGE BEHIND IT BUILDS AND THE OVERALL PATTERN BECOMES MORE
AMPLIFIED. MOST OF THE GUIDANCE HAS COME AROUND TO THE IDEA OF A
STRONG VORTICITY CENTER/AND OR MID LEVEL CIRCULATION DEVELOPING OVER
ERN ID OR WRN WYO SATURDAY NIGHT AND THEN SHIFTING OFF TO THE SE
LATER SUNDAY. 12Z NAM CAME STRONGLY BACK TO THIS IDEA AGAIN WITH
BEST FORCING BACK IN CENTRAL WYOMING AND NOT JUST THE FAR NORTH. NEW
12Z ECMWF CONTINUES IT CONSISTENT TRACK AND STRONG UPSLOPE IDEA EAST
OF THE DIVIDE. FORCING LOOKING FAIRLY DECENT WITH THIS SYSTEM WITH
THE POTENTIAL FOR DUAL JET STRUCTURE SUPPORT AS CURVED CYCLONIC JET
NOSES INTO THE WEST AT THE SAME TIME THAT AN EXITING JET IS OVER THE
HIGH PLAINS. THAT POTENTIAL COMBO ALONG WITH THE MID LEVEL
CIRCULATION AND INCREASING QG FORCING SHOULD PRODUCE RAPIDLY
DEVELOPING PCPN SATURDAY EVENING CHANGING OVER TO SNOW UP NORTH
FIRST AND FURTHER SOUTH IN FREMONT AND NATRONA LATER IN THE EVENING
OR TOWARDS MIDNIGHT. WE ALSO HAVE THE POTENTIAL FOR SOME HEAVIER
MESOSCALE BANDING WITH FAIRLY STRONG FRONTOGENESIS AND MID LEVEL
DEFORMATION IN A FAVORABLE LOCATION FOR FREMONT COUNTY AND
POTENTIALLY NATRONA. THE BEST COMBINATION OF UPSLOPE AND DYNAMICS IS
FREMONT AND THE SERN ABSAROKAS AND FOOTHILL AREAS THOUGH. NOT THE
LONGEST LASTING SNOWSTORM BUT A GOOD 9 HOURS OR SO OF GOOD SNOW WITH
SOME LIGHTER SNOW LINGERING INTO SUNDAY AFTERNOON. POTENTIAL FOR A
COUPLE WINTER STORM WATCHES DO EXIST IF TRENDS CONTINUE...ESPECIALLY
FOR THE LANDER FOOTHILLS AND EAST SLOPE OF THE WINDS BUT EVEN THE
SRN ABSAROKAS AND NEARBY FOOTHILLS COULD BE INTERESTING. ADVISORIES
WILL PROBABLY BE SUFFICIENT FOR MOST OF THE SURROUNDING AREAS WITH
TIME. STILL A CHANCE THOUGH THAT THE WIND RIVER BASIN WILL NEED A
WATCH DEPENDING ON HOW OUR MESOSCALE BANDING AND OVERALL DYNAMICS
LOOK AS WE GET CLOSER TO THE EVENT.

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY

A REENFORCING SHOT ON THE BACK SIDE OF THE TROUGH WILL KEEP SOME
SNOW AROUND THROUGH SUNDAY EVENING WITH GRADUAL CLEARING FROM
NORTHWEST TO SOUTHEAST EARLY MONDAY MORNING AS RIDGING BUILDS IN
FROM THE WEST. THERE COULD BE SOME AREAS OF FOG ACROSS THE NORTH
AS SKIES CLEAR ON MONDAY MORNING WITH MORE WIDESPREAD FOG LATE
MONDAY NIGHT INTO TUESDAY AS HIGH PRESSURE TAKES OVER AND WAA
ENVELOPS THE AREA. THERE WILL BE QUITE A BIT OF MELTING AND SOME
TEMPERATURE REBOUND ON TUESDAY AND WEDNESDAY AS THE RIDGE TAKES
OVER. THE NEXT STORM SYSTEM COULD BE APPROACHING AS EARLY AS
TUESDAY NIGHT. THERE IS SOME SIGNIFICANT MODEL DISAGREEMENT ON
THIS NEXT SYSTEM SO WENT WITH VERY BROAD SLIGHT CHANCE POPS WITH
LOCALLY HIGHER POPS WHEN AND WHERE THE MODELS TRY TO COME
TOGETHER. EITHER WAY...THE TRACK OF THIS STORM COULD BE
POTENTIALLY FAVORABLE FOR ANOTHER SNOW EVENT EAST OF THE
DIVIDE...WITH SOME RAIN POSSIBLE EARLY IN THE STORM.

&&

.AVIATION.../00Z ISSUANCE/

VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH SOME OCCNL MTN
OBSCURATIONS AND SPRINKLES THROUGH THE EVENING ACROSS THE FAR
WEST. WINDS WILL BE GUSTY AT TIMES THROUGH THE
AFTERNOON...TAPERING OFF AFTER SUNSET. WINDS WILL INCREASE AGAIN
FROM KRKS TO KCPR AND OVER MTN TOPS AFTER 17Z FRI...CONTINUING
THROUGH THE END OF THE PERIOD. WINDS COULD GUST OVER 25KT AT THE
TERMINALS MENTIONED AND OVER 40KTS OVER HIGHER TERRAIN.

&&

.FIRE WEATHER...

STRONG NORTHWEST FLOW ALOFT OVER THE AREA WILL PRODUCE MILD AND DRY
CONDITIONS BUT ALSO PERIOD OF GUSTY TO STRONG WIND...ESPECIALLY IN
THE AFTERNOON AND EVENING HOURS AND MOST OF THE TIME IN THE
MOUNTAINS AND FOOTHILL AREAS. IT WILL BE QUITE DRY ON FRIDAY AFTERNOON
WITH MINIMUM RH`S IN THE 12 TO 17 PERCENT RANGE FOR MANY AREAS
EAST OF THE DIVIDE AND DOWN INTO SWEETWATER COUNTY. THIS LOW RH
AND GUSTY WIND WILL INCREASE THE FIRE POTENTIAL...ESPECIALLY FOR
ANY PLANNED DITCH BURNS...ETC.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...SKRBAC
LONG TERM...ALLEN
AVIATION...ALLEN
FIRE WEATHER...SKRBAC










USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.