Severe Thunderstorm Warning 10, NWS Grand Junction, CO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
335 PM MDT WED MAY 27 2015

.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 332 PM MDT WED MAY 27 2015

RADAR THIS AFTERNOON A BIT MORE SUBDUED COMPARED TO 24 HOURS AGO.
HOWEVER UPSTREAM MOSAIC SHOWS PLENTY OF ACTION ASSOCIATED WITH A A
PV LOBE ROTATING INTO THE NORTHERN GREAT BASIN...AROUND THE PARENT
LOW OVER THE NORTHERN ROCKIES. VORTICITY IS BEING ENHANCED BY THE
EXIT REGION OF A JET LEVEL SPEED MAX WHICH IN TURN IS TIGHTENING A
MID LEVEL CIRCULATION DROPPING THROUGH OUR NORTHERN CWA LATE THIS
EVENING. CONDITIONAL INSTABILITY IN THE ELEVATED MIXED LAYER
OVERNIGHT LOOKS TO BE RELEASED BY THE FRONTO BAND AND KEPT THE
HIGHEST POPS RUNNING NORTH OF INTERSTATE 70 THROUGH SUNRISE.
ISOLATED STORMS WILL BE POSSIBLE ELSEWHERE BUT CONFIDENCE NOT AS
HIGH AND POPS WILL BE TRENDING DOWNWARD AFTER SUNSET. LOWS TONIGHT
LOOK A BIT MILDER THAN THE PAST FEW NIGHTS.

THURSDAY THE TROUGH DIGS THROUGH THE GREAT BASIN AND LINGERS OVER
THE FORECAST AREA THROUGH THURSDAY NIGHT. AFTERNOON AND EVENING JET
SUPPORT OVER A SURFACE COLD FRONT WILL SUPPORT WIDESPREAD SHOWERS
AND STORMS NORTH OF I-70. A FEW THOSE STORMS WILL BE CAPABLE OF
PRODUCING HAIL AND STRONG GUSTY WINDS. STORM INTENSITY IS
EXPECTED TO DIMINISH AFTER SUNSET BUT SOME STORMS MAY CONTINUE
THROUGH THE NIGHT.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 332 PM MDT WED MAY 27 2015

A QUICK AND DRAMATIC TRANSITION FROM COOL TO WARM IS EXPECTED
THROUGH MONDAY.

TEMPERATURES HAVE BEEN RUNNING BELOW NORMAL FOR MUCH OF MAY BUT
WILL QUICKLY TRANSITION TO 5-10 DEGREES ABOVE NORMAL BY MONDAY.
THE CULPRIT IS A BUILDING RIDGE FROM THE SW THAT WILL WORK
OVERHEAD BY SUNDAY.

FRIDAY...SHOWERS AND STORMS WILL CONTINUE MAINLY ALONG THE
EASTERN CWA. FRIDAY NIGHT A FRONT RANGE COOL FRONT WILL BACK UP
AGAINST THE CONTINENTAL DIVIDE AND MAY KEEP SHOWERS GOING
OVERNIGHT IN THE EASTERN PORTIONS OF THE SAN JUANS AND THE PAGOSA
SPRINGS AREA. MOISTURE AND STORM COVERAGE ERODE SATURDAY AND
SUNDAY AS VERY WARM TEMPERATURES ALOFT LIMIT INSTABILITY.

MOUNTAIN SNOW PACK WILL GO THROUGH A PERIOD OF STRONG MELTING
BEGINNING SATURDAY...WITH OVERNIGHT LOW TEMPS STAYING ABOVE
FREEZING. EXPECT A RISE IN STREAM AND RIVER LEVELS INTO NEXT WEEK.

TUESDAY-WEDNESDAY THE RIDGE IS FLATTENED AS THE NEXT PACIFIC
TROUGH WORKS THROUGH THE NORTHERN ROCKIES. ABOVE NORMAL
TEMPERATURES CONTINUE. MOISTURE WILL BE QUITE LIMITED UNTIL
PERHAPS WEDNESDAY AFTERNOON WITH SHOWERS RETURNING TO THE NORTH.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1049 AM MDT WED MAY 27 2015

A SHORT BREAK IN THE SHOWER AND THUNDERSTORM ACTIVITY THIS MORNING
IS LEAVING VFR CONDITIONS ACROSS THE FORECAST TERMINALS. HOWEVER
SOME CLOUD COVER HUGGING THE DIVIDE PEAKS ARE LEADING TO AREAS OF
TERRAIN OBSCURATION. AFTERNOON HEATING AND PLENTY OF REMAINING
MOISTURE WILL AGAIN LEAD TO SCATTERED AFTERNOON SHOWERS WITH
EMBEDDED THUNDERSTORMS. EXACT TIMING IS DIFFICULT BUT 27/20Z TO
28/04Z WILL BE THE PERIOD OF THE MOST ACTIVITY. THE MAIN THREATS
WILL BE GUSTY...ERRATIC WINDS AND LIGHTNING. FLIGHT CRITERIA COULD
BE TEMPORARILY DECREASED BY SHOWERS PASSING OVER THE FLIGHT
TERMINALS. SHOWERS WILL REMAIN OVER NORTHERN UTAH AND COLORADO
OVERNIGHT...OTHERWISE CLEARING IS EXPECTED ELSEWHERE.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&

SHORT TERM...15/JOE
LONG TERM...JOE
AVIATION...TGJT