Weather Service Report


910 
FXUS65 KRIW 010834
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
234 AM MDT FRI AUG 1 2014

.SHORT TERM...TODAY THROUGH SUNDAY NIGHT

HIGH PRESSURE REMAINS OVER THE FORECAST AREA TODAY...THOUGH THE AXIS 
OF THE RIDGE IS NOT CLEARLY DEFINED IN THE CURRENT PATTERN. A SURGE 
OF MOISTURE RETURNS TO THE FORECAST AREA DURING THE AFTERNOON HOURS. 
EXPECT SHOWERS TO GENERALLY IMPACT WESTERN AND NORTHERN 
WYOMING...THOUGH A FEW AREAS OF SOUTHERN WYOMING MAY ALSO SEE SOME 
ACTIVITY DURING THE LATE AFTERNOON AND EARLY EVENING PERIODS.
STORMS MAY CONTAIN PERIODS OF HEAVY RAINFALL... WITH SOME
POTENTIAL EXISTING FOR FLOODING. EVEN WITH THE ANTICIPATED STORM
COVERAGE...EXPECT TEMPERATURES TO BE WARMER TODAY ACROSS MUCH OF
THE FORECAST AREA.

SIMILAR CONDITIONS EXPECTED OVER THE NEXT FEW DAYS...ESPECIALLY 
CONCERNING AFTERNOON SURGES OF MOISTURE. AFTERNOON SHOWERS AND 
THUNDERSTORMS WILL BE PRESENT THROUGH THE MAJORITY OF THE SHORT TERM 
FORECAST PERIOD. THE RIDGE OF HIGH PRESSURE WILL WORK TO BECOME MORE 
ORGANIZED AS IT MOVES EASTWARD. THE AXIS OF THE RIDGE IS GENERALLY 
EXPECTED TO MOVE OVER WESTERN WYOMING BY SATURDAY AFTERNOON. 

WITH THE CONTINUED INFLUENCE OF THE RIDGE OF HIGH PRESSURE...EXPECT 
TEMPERATURES TO GENERALLY WARM THROUGH THE PERIOD. 
ADDITIONALLY...WIND IS EXPECTED TO REMAIN LIGHT. 

.LONG TERM...MONDAY THROUGH FRIDAY

MODELS STRUGGLING WITH THE POTENTIAL SIGNIFICANT SHORTWAVE THAT IS 
EXPECTED TO ROTATE AROUND THE BOTTOM OF THE MONSOONAL HIGH AND THEN 
LIFT NWD OVER OR NEAR US EARLY NEXT WEEK. THE GFS HAS BEEN MOST 
CONSISTENT WITH THE BRUNT OF THE UPPER LOW/TROUGH LIFTING NWD INTO 
THE NRN GREAT BASIN MONDAY AND THEN MOVING EAST ACROSS OUR AREA 
TUESDAY. THE GEM IS SIMILAR JUST SLOWER IN ITS EVOLUTION. THE ECMWF 
TONIGHT IS LIFTING THE SHORTWAVE ALL THE WAY INTO MONTANA BEFORE 
MOVING IT E AND THEN SEWD BACK OVER US ON WEDNESDAY. LAST NIGHT THE 
ECMWF KEPT THE BRUNT OF THE ENERGY OVER COLORADO. A FEW GFS 
ENSEMBLES DO THIS ALSO. THE 12Z ECMWF ENSEMBLES WERE GENERALLY 
FURTHER SOUTH OVER WYOMING. GENERALLY SIDING WITH THE MORE 
CONSISTENT OP GFS TRACK TONIGHT. EVEN THOUGH THE SHORTWAVE ENERGY 
TRACKS ARE ALL OVER THE PLACE...THEY ALL ARE SHOWING A SIGNIFICANT 
LOW AND MID LEVEL MOISTURE SURGE WITH SURFACE DEW POINTS CLIMBING 
WELL INTO THE 50S MONDAY INTO MONDAY NIGHT. WILL GO WITH INCREASING 
POPS IN THE SW HALF TO START THE PERIOD...GRADUALLY SHIFTING EWD BY 
MONDAY EVENING. MONDAY NIGHT AND TUESDAY SHOULD SEE MANY AREAS WITH 
A GOOD CHANCE OF RAIN/SHOWERS AND ONLY A FEW THUNDERSTORMS. AIRMASS 
IS MORE TROPICAL IN NATURE WITH WARMER TEMPERATURES ABOVE H5 LEADING 
TO LIMITED INSTABILITY AND THUS MORE SHOWERY LIKE OUR LAST EVENT. 
HEAVY RAIN IS DEFINITELY POSSIBLE AGAIN WITH THIS PATTERN. NW FLOW 
DEVELOPS BEHIND THIS DISTURBANCE WITH SCT MTN STORMS STILL EXPECTED 
WEDNESDAY AND ISOLATED LOWER ELEVATION SHOWERS...ESPECIALLY DOWNWIND 
OF THE MOUNTAIN RANGES. THURSDAY WILL SEE A FEW SHOWERS AND 
THUNDERSTORMS BUT MAINLY OVER THE HIGH COUNTRY. ON FRIDAY...A NEW 
UPPER LEVEL LOW WHICH IS EXPECTED TO MOVE IN FROM OFF THE CA COAST 
MAY GET CAUGHT IN THE CIRCULATION AROUND THE MONSOONAL HIGH. THE 
APPROACH OF THIS SYSTEM FRIDAY WILL LIKELY RESULT IN ANOTHER SHOT OF 
INCREASING SHOWERS AND THUNDERSTORMS. THIS SYSTEM LOOKS TO HAVE 
COLDER AIR ALOFT AND MORE INSTABILITY FOR THUNDERSTORMS. SO DECENT 
POTENTIAL FOR A WET START AND END TO THE MEDIUM RANGE PERIOD. 
TURNING COOLER TO START THE PERIOD WITH A MID WEEK WARM UP AND THEN 
COOLER IN THE WEST AGAIN ON FRIDAY.

&&

.AVIATION.../12Z ISSUANCE/

EAST OF THE CONTINENTAL DIVIDE...KCPR/KRIW/KLND/KWRL/KCOD

VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. SHOWERS AND STORMS 
WILL FORM OVER AND NEAR THE MOUNTAINS AFTER 19Z AND CONTINUE THROUGH 
02Z. A FEW OF THE STORMS AND SHOWERS WILL DRIFT SOUTHEAST ACROSS THE 
LOWER ELEVATIONS DURING THE AFTERNOON AND EARLY EVENING HOURS. MOST 
TERMINAL SITES WILL NOT BE IMPACTED DIRECTLY BY THIS ACTIVITY. SEE 
INDIVIDUAL TERMINAL FORECASTS FOR MORE DETAILS. 

WEST OF THE CONTINENTAL DIVIDE...KJAC/KBPI/KPNA/KRKS

VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. SHOWERS AND STORMS 
WILL FORM OVER AND NEAR THE MOUNTAINS AFTER 18Z AND CONTINUE THROUGH 
03Z. A FEW OF THE STORMS AND SHOWERS WILL DRIFT EAST OR SOUTHEAST 
ACROSS THE LOWER ELEVATIONS DURING THE AFTERNOON AND EARLY EVENING 
HOURS. TERMINAL SITES MAY BE IMPACTED BY THIS ACTIVITY...SEE 
INDIVIDUAL TERMINAL FORECASTS FOR MORE DETAILS. 

&&

.FIRE WEATHER...

HIGH PRESSURE OVER THE FORECAST AREA WILL KEEP WARMING TEMPERATURES 
PRESENT FOR THE NEXT COUPLE DAYS...AS WELL AS GENERALLY LIGHT WIND. 
EMBEDDED MOISTURE WILL CONTINUE THE TREND OF AFTERNOON SHOWERS AND 
THUNDERSTORMS. MOST ACTIVITY IS EXPECTED TO IMPACT NORTHERN AND 
WESTERN WYOMING...THOUGH SOME SHOWER ACTIVITY MAY IMPACT ADDITIONAL 
AREAS EAST OF THE DIVIDE DURING THE FORECAST PERIOD.

&&

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

&&

$$

SHORT TERM...BRANHAM
LONG TERM...SKRBAC
AVIATION...AR
FIRE WEATHER...BRANHAM











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