National Weather Service Forecast Discussion

000
FXUS65 KBOU 112048
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
150 PM MST THU MAR 11 2010

.SHORT TERM...TIGHT WEST-EAST PRESSURE GRADIENT ACROSS THE PLAINS
WILL CONTINUE TO PRODUCE PERIODS OF STRONG AND GUSTY N-NWLY SFC
WINDS DURING THE SHORT-TERM. MAY ACTUALLY SEE SPEEDS RAMPING UP
ACROSS THE NERN CORNER OF THE STATE LATER THIS AFTERNOON AND EARLY
THIS EVENING IN RESPONSE TO AN INCREASE IN SUBSIDENCE AND NWLY FLOW
ALOFT. SHOULD THEN SEE SFC WINDS SLACKEN OFF OVERNIGHT WITH
DECOUPLING OF THE BOUNDARY LAYER ONLY TO STRENGTHEN AGAIN FRIDAY
MORNING. NAM AND GFS WIND CROSS SECTIONS INDICATE A NWLY WND
COMPONENT OF 45-50KTS JUST OFF THE SFC EARLY FRIDAY MORNING OUT NEAR
THE NERN CORNER. SO MAY NOT BE TOO LONG AFTER SUNRISE BEFORE WE SEE
30-40KT SFC WNDS DEVELOPING ON THE PLAINS AGAIN...GENERALLY EAST OF
A GREELEY TO LIMON LINE. OTHERWISE THE FEW REMAINING -SHSW UP ALONG
THE CONTINENTAL DIVIDE SHOULD PRETTY MUCH COME TO AN END AROUND
SUNSET AS SUBSIDENCE AND DRIER AIR ADVECTS IN FROM THE NRN GREAT
BASIN. TEMPERATURES NEXT 24 HOURS WILL BE ON THE RISE AFTER A CHILLY
NIGHT TONIGHT UNDER CLEAR SKIES. LOOKING FOR MAX TEMPERATURES TO
FINALLY RETURN TO NEAR AVERAGE WITH WARMEST READINGS FOUND IN THE
I-25 URBAN CORRIDOR.


.LONG TERM...WEAK HIGH PRESSURE ALOFT WILL MOVE ACROSS THE STATE FRI
NIGHT AND SATURDAY WITH DRY AND WARMER CONDITIONS. THE NORTHWEST
WINDS WILL FINALLY DIMINISH OVER THE NORTHEAST PLAINS FRI EVENING AS
THE SFC GRADIENT RELAXES. THE NEXT STORM SYSTEM WILL TRACK FROM THE
GREAT BASIN AND MOVE SOUTHEAST TOWARDS THE 4 CORNERS REGION BY
SUNDAY MORNING. CLOUDS AND LIGHT SHOWERS WILL BEGIN TO SPREAD
EASTWARD ACROSS WESTERN PORTIONS OF THE STATE ON SAT NIGHT AND EARLY
SUNDAY.

EVEN THOUGH THE LONG RANGE MODELS HAVE THE GENERAL TRACK OF THE LOW
TO THE SOUTH AND SOUTHEAST OVER THE GREAT BASIN...THE EXACT
POSITIONS VARY ENOUGH WHICH WILL EFFECT THE OUTCOME FOR OUR WEATHER
ON SUNDAY AND MONDAY. THERE IS A WEAK SURFACE FRONT WHICH WILL SHIFT
THE WINDS UPSLOPE ON SUNDAY AFTERNOON WHICH WILL HELP IN THE
SATURATION PROCESS ON THE EAST SLOPES AND ADJACENT PLAINS.
STILL...MUCH OF THE UPWARD ASCENT FROM THE LOW REMAINS WELL SOUTH OF
THE CWA AND RESULTING PRECIP POTENTIAL. THE EAST SLOPES MAY STILL
HAVE A DECENT SHORT LIVED CHANCE OF PRECIP ON EARLY SUNDAY BEFORE
THE LOW MOVES INTO SOUTHERN NEW MEXICO ON SUNDAY NIGHT AND MONDAY.
APPEARS THE BEST CHANCES OF PRECIP WILL BE ON THE EAST SLOPE
SOUTHERN FRONT RANGE FOOTHILLS AND WESTERN PALMER DIVIDE. AT THIS
TIME...TEMPERATURES WOULD BE WARM ENOUGH ON THE PLAINS FOR MAINLY
RAIN SHOWERS AND A MIX OF RAIN/SNOW IN THE FOOTHILLS. FOR MONDAY
THERE IS A WEAK WAVE THAT RUNS UP AND OVER THE RIDGE AND DIVES DOWN
THE AMPLIFIED RIDGE WHICH MIGHT PRODUCE SOME ADDITIONAL SHOWERS.
CURRENT CHANGES TO WEATHER GRIDS INCLUDE A SLIGHT INCREASE IN POPS
OVER THE EAST SLOPES WHILE MAINTAINING VERY LOW POPS ON THE
NORTHEAST PLAINS.

STILL LOOKING AT A DRY AND WARMING TREND FOR TUE-WED TIME FRAME WITH
RIDGING ALOFT OVER THE REGION. EXPECT MORE UNSETTLED WEATHER TO
RETURN TOWARDS THE END OF NEXT WEAK WITH ADDITIONAL ENERGY MOVING
INTO THE WESTERN U.S.

&&

.AVIATION...GUSTY NORTH-NORTHWEST WILL REMAIN AS THE PRINCIPLE
WEATHER CONCERN REST OF THIS AFTERNOON AND EARLY THIS EVENING. A
TIGHT PRESSURE GRADIENT AND STRONG NORTHWEST FLOW ALOFT WILL
CONTINUE TO PRODUCE 20-30KT WINDS IN AREAS EAST OF I-25 THROUGH 01Z
THIS EVENING. ONCE THE SUN SETS FORMATION OF THE NIGHT TIME SURFACE
INVERSION SHOULD REDUCE WIND SPEEDS TO UNDER 20KTS. ON FRIDAY...
LIGHT WEST TO NORTHWEST WINDS IN THE MORNING ARE EXPECTED TO
STRENGTHEN AGAIN AROUND MIDDAY...ALTHOUGH SPEEDS AT DIA ARE NOT
EXPECTED TO BE AS GREAT AS THOSE OBSERVED TODAY. OTHERWISE DRY AND
STABLE CONDITIONS WILL PREVAIL THROUGH THE PERIOD.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...NONE

$$
BAKER/ENTREKIN

NWS BOU Office Area Forecast Discussion