000
FXUS65 KPUB 172136
AFDPUB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PUEBLO CO
336 PM MDT SAT MAY 17 2008
.SHORT TERM...
(TONIGHT AND SUNDAY)
CURRENTLY GUSTY NORTH WINDS BEHIND WEAK SURFACE BOUNDARY HAVE HELPED
TO REDUCE RH ACROSS SOUTHEAST PLAINS TO BELOW 15 PERCENT. WINDS
HAVE HELD STRONGER FOR A LONGER PERIOD THAN EXPECTED. ISSUED RED
FLAG WARNING FOR FW ZONES 227, 228 AND 231>236 UNTIL 01Z.
TONIGHT...EXPECT WINDS TO DECREASE AFTER SUNSET WHICH ALONG WITH
RECOVERING RH SHOULD REDUCE POTENTIAL FOR CRITICAL FIRE WEATHER
CONDTIONS. WARM UPPER RIDGE CONTINUES TO BUILD INTO THE REGION AND
WHILE WINDS WILL DECREASE TONIGHT TEMPS WILL BE WARMER THE LAST
NIGHT AND RH RECOVERY LESS. RAISED TEMPS A FEW DEGREES DUE TO THE
CONTINUED WARM ADVECTION ALOFT.
SUNDAY...CONCERNS RETURN FOR CRITICAL FIRE WEATHER CONDITIONS.
AFTERNOON TEMPS WILL BE SEVERAL DEGREES WARMER ESPECIALLY ACROSS
THE PLAINS. NOT MUCH RECOVERY FOR THE DEW POINTS SO EXPECT LESS THAN
15 PERCENT RH ALONG WITH SOME GUSTY WINDS FOR THE AFTERNOON TO EARLY
EVENING. HAINES INDEX VALUES AT 5 OR 6 AS WELL SO WILL ISSUE FIRE
WEATHER WATCH FOR SLV TO KS BORDER FOR SUNDAY AFTN AND EVENING.
-FORTUNE-
.LONG TERM...
(SUNDAY NIGHT THROUGH NEXT SATURDAY)
STILL LOOKS HOT MONDAY WITH UPPER RIDGE...DOWNSLOPE AND 700 MB TEMPS
IN THE 12-16C RANGE. PROBABLY NOT ENOUGH WIND FOR CRITICAL FIRE WEATHER
CONDITIONS...THOUGH RH WILL CERTAINLY BE LOW ENOUGH FOR CONCERN. WEAK
COLD FRONT BACKS INTO THE PLAINS MONDAY NIGHT...THEN WASHES OUT
TUESDAY WITH WEAK LEE TROUGH FORMING. DIDN`T JUMP ON THE COOLER
GUIDANCE TEMPS YET FOR TUE AFTERNOON...AS WARM AIR IS LURKING JUST
TO THE WEST AND WILL SPREAD BACK OVER THE AREA BY AFTERNOON. WITH RH
CREEPING UP OVER THE PLAINS AND WINDS REMAINING MODERATE...STILL
LOOKING AT FIRE WEATHER CONDITIONS REMAINING JUST BELOW CRITICAL
LEVELS. FIRE WEATHER CONCERNS INCREASE WED AS MID LEVEL FLOW
INCREASES AND DRYLINE SETS UP OVER THE FAR EASTERN PLAINS. AREA FROM
I-25 AND WESTWARD LOOKS TO BE WELL INTO CRITICAL CONDITIONS...WITH
PLAINS DEPENDING ON ULTIMATE FATE OF THE DRYLINE. COULD BE TOO
CAPPED OVER THE EAST FOR TSRA...WE`LL SEE. BOOSTED TEMPS UP
CONSIDERABLY FOR WED...MAY NEED TO GO EVEN WARMER IF GFS IS CORRECT.
12Z GFS AND ECMWF CONTINUE TO TREND WESTWARD WITH THE MASSIVE UPPER
TROUGH OVER THE WESTERN U.S LATE NEXT WEEK...WITH BOTH MODELS NOW
CUTTING OFF A SUBSTANTIAL PIECE ENERGY OVER THE SOUTHWEST WAITING
UNTIL WELL INTO THE WEEKEND TO EJECT IT. WITH THE SLOWER SPEED OF
THE TROUGH...COLD FRONT NOW APPEARS TO REMAIN NORTH OF THE AREA
THROUGH AT LEAST SATURDAY...WITH SURFACE LOW PRESSURE TAKING UP
RESIDENCE IN EASTERN COLORADO THROUGH THE PERIOD. HAD TO WARM TEMPS
SIGNIFICANTLY IN THE WED-FRI TIME PERIOD...THOUGH STILL HELD BACK ON
GOING AS WARM AS THE MEX GUIDANCE...AS BOUNDARY WILL BE CLOSE BY.
GIVEN THE FARTHER WEST POSITION OF THE UPPER LOW AND THE LACK OF ANY
SIGNIFICANT WESTERLY COMPONENT TO THE MID LEVEL FLOW...SUSPECT ECMWF
IS CORRECT IN KEEPING THE DRYLINE WEST OF THE KANSAS/COLORADO
BORDER...WHILE GFS IS TOO FAR EAST WITH THE BOUNDARY OVER KANSAS
DESPITE LITTLE IN THE WAY OF FORCING TO GET IT THERE. STRONG 0-6KM
SHEAR SUGGESTS A MULTIPLE DAY RUN OF SEVERE WEATHER ON THE PLAINS
WED-SAT IF...AND IT`S A BIG IF...WE CAN OVERCOME CAPPING INVERSION
AND INITIATE STORMS...WHICH MIGHT BE DIFFICULT IF THE UPPER TROUGH
AND JET REMAIN AS FAR WEST AS MODELS PROG. BROADBRUSH OF TSRA FOR
THE PLAINS THROUGH THE PERIOD REMAINS IN PLACE FOR NOW...STAY TUNED.
OVER THE MOUNTAINS...FARTHER WEST POSITION OF THE TROUGH PROBLEMATIC
AS BEST FORCING FOR PRECIP APPEARS TO BE WEST OF THE CONTINENTAL
DIVIDE THROUGH THE END OF THE WEEK...WITH PERHAPS AN UPTICK IN
PRECIP CHANCES OVER THE HOLIDAY WEEKEND AS LOW SLOWLY EJECTS
EASTWARD. WILL MAINTAIN JUST LOW POPS FOR NOW AND SEE HOW MODEL RUNS
UNFOLD. EASTERN MOUNTAINS AND I-25 CORRIDOR MAY END UP IN BETWEEN
WEATHER REGIMES...WITH PRECIP ALONG THE CONTINENTAL DIVIDE AND
STORMS ON THE PLAINS. FIRE WEATHER CONCERNS COULD PERSIST OVER MOST
OF THE EASTERN MOUNTAINS FROM WED INTO FRI IF DRY SLOT SETS UP AS
PROGGED...THOUGH CONVECTIVE DEVELOPMENTS ON THE PLAINS WILL HAVE THE
FINAL SAY ON WHERE LOW LEVEL MOISTURE ENDS UP. OF COURSE THIS WHOLE
SCENARIO COULD CHANGE WITH JUST A MINOR WOBBLE OF THE UPPER
TROUGH...AND WOULD EXPECT SEVERAL OF THESE TO APPEAR IN THE MODELS
THE NEXT FEW DAYS. --PETERSEN
&&
.AVIATION...
GUSTY WINDS WILL CONTINUE UNTIL AFTER SUNSET THEN SHOULD SETTLE DOWN
OVERNIGHT WITH PREVAILING VFR CONDITIONS THROUGH SUNDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ227-228-231-
232-234>236.
FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR COZ222-224-225-227>237.
&&
$$
21/10
