No watches are valid as of Mon Sep 6 10:40:02 UTC 2010.

No Mesoscale Discussions are in effect as of Mon Sep 6 10:40:02 UTC 2010.

Day 4-8 Outlook

DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0356 AM CDT MON SEP 06 2010

VALID 091200Z - 141200Z

...DISCUSSION...
AMPLE AGREEMENT CONTINUES AMONG 00Z ECMWF/GEFS GUIDANCE ASIDE FROM
RELATIVELY MINOR TIMING/MAGNITUDE DIFFERENCES INTO THE WEEKEND. THE
MAIN FOCUS WILL BE ON THE NORTHEASTWARD EJECTING WESTERN STATES
TROUGH ON DAYS 4/5...AS IT INTERACTS WITH A BROAD WARM/MOIST SECTOR
ACROSS THE NORTHERN AND CENTRAL PLAINS TO MIDWEST. THE REMNANTS OF
CURRENT TROPICAL SYSTEM HERMINE MAY ALSO BE A FACTOR INTO DAY
4/THURSDAY ACROSS THE SOUTH-CENTRAL PLAINS/OZARKS VICINITY...BUT A
CONSIDERABLY LIMITED FORECAST PREDICTABILITY EXISTS BY THIS TIME
FRAME /REFERENCE LATEST NHC FORECASTS/.

WITH THE ADVANCEMENT OF THE WESTERN STATES UPPER TROUGH OVER THE
NORTH CENTRAL STATES...A SEVERE THREAT IS EXPECTED TO INCREASE BY
DAY 4/THURSDAY ACROSS THE NORTHERN HIGH PLAINS...INCLUDING THE
WESTERN DAKOTAS TO WESTERN/NORTHERN NEB. WHILE LARGE SCALE TIMING
UNCERTAINTY INCREASES SOMEWHAT INTO DAY 5/FRIDAY...IT IS PROBABLE
THAT A SEVERE RISK WILL EXIST WITHIN A CORRIDOR ACROSS THE EASTERN
DAKOTAS/MIDDLE MO VALLEY TO THE UPPER MS VALLEY/UPPER
MIDWEST...PERHAPS CENTERED ACROSS EASTERN SD/EASTERN NEB TO
IA/SOUTHERN MN. LARGE SCALE TIMING UNCERTAINTY/INHERENT MODEL
VARIABILITY...ALONG WITH THE POSSIBILITY OF A SOMEWHAT ANA-FRONTAL
TYPE SCENARIO BY DAY 5...PROVIDES UNCERTAINTY REGARDING THE
MAGNITUDE OF SPECIFIC DAY SEVERE POTENTIAL. WHILE CATEGORICAL SEVERE
RISKS ARE A DISTINCT POSSIBILITY FOR DAY 4/THURSDAY AND DAY
5/FRIDAY...DELINEATION OF ANY HIGHER PROBABILITY /30 PERCENT AND
GREATER/ RISK AREAS ARE NOT CURRENTLY WARRANTED.

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SPC Day 1 Fire Weather Outlook

DAY 1 FIRE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0236 AM CDT MON SEP 06 2010

VALID 061200Z - 071200Z

...NO CRITICAL AREAS...

...SYNOPSIS...
A VIGOROUS UPPER-LEVEL SHORT WAVE TROUGH WILL PROGRESS EWD FROM THE
NRN HIGH PLAINS/CNTRL ROCKIES TOWARDS THE UPPER MS VALLEY THROUGH
EARLY TUE. ATTENDANT SURFACE CYCLONE OVER THE CNTRL HIGH PLAINS WILL
TRACK NEWD TO MN...WHILE A COLD FRONT PUSHES SEWD ACROSS THE CNTRL
HIGH PLAINS INTO THE OK/TX PANHANDLES BY EARLY EVENING. IN THE
WEST...AN UPPER-LEVEL SHORT WAVE TROUGH WILL DIG ALONG THE BRITISH
COLUMBIA COAST WITH A SURFACE RIDGE WEAKENING OVER THE PACIFIC NW.

...SERN WY/N-CNTRL CO E/SEWD ACROSS THE CNTRL HIGH PLAINS...
AREAS OF SHORT-DURATION CRITICAL CONDITIONS TO LONGER-DURATION
MARGINAL CONDITIONS APPEAR PROBABLE FROM LATER THIS MORNING INTO THE
AFTERNOON. RELATIVELY LARGE SPREAD PERSISTS AMONGST LATEST
NAM/GFS/SREF GUIDANCE WITH THE DEGREE OF DRYING OCCURRING IN THE
WAKE OF A COLD FRONT PASSAGE THIS MORNING. 00Z NAM AND 03Z SREF MEAN
INDICATE CRITICALLY LOW RH VALUES WILL BE RELEGATED TO ALONG THE LEE
OF THE FRONT RANGE IN N-CNTRL CO...WHILE THE 00Z GFS SUGGESTS LOW RH
WILL ALSO BE PREVALENT TO THE N/E ACROSS SERN WY INTO WRN NEB/KS.
MODEL FORECASTS ARE MORE CONSISTENT WITH THE DEPICTION OF A SURGE IN
LOW-LEVEL W/NWLYS ACCOMPANYING SHORT WAVE TROUGH PASSAGE LATER THIS
MORNING. THIS SHOULD LEAD TO A FEW HOURS OF CRITICAL CONDITIONS
AROUND NOON ALONG THE FRONT RANGE IN N-CNTRL CO...PRIOR TO WINDS
DIMINISHING THROUGH THE AFTERNOON AS A SURFACE RIDGE QUICKLY BUILDS
ACROSS THE HIGH PLAINS. FARTHER E INTO WRN NEB/KS...LONGER DURATIONS
OF STRONG N/NWLY WINDS /FROM 20 TO 30 MPH/ APPEAR LIKELY.
HOWEVER...BASED ON UPSTREAM OBSERVATIONS OF MUCH COOLER/HIGHER RH
VALUES...AFTERNOON RH VALUES MAY ONLY BECOME MARGINALLY LOW /FROM 20
TO 30 PERCENT/.

...SERN MO...NERN AR...SRN IL/IND...WRN KY/TN...
AN ENHANCED FIRE WEATHER THREAT SHOULD DEVELOP THIS AFTERNOON
AS SLY SURFACE WINDS INCREASE WITHIN AN ANTECEDENT WARM/DRY AIR MASS
ACROSS THE LOWER MS/OH VALLEY...WHERE ABNORMAL DRYNESS AND MODERATE
DROUGHT PERSIST. MODEL FORECASTS REMAIN HIGHLY CONSISTENT THAT
TEMPERATURES WILL WARM INTO THE MIDDLE TO UPPER 80S...WITH RH VALUES
DROPPING TO BETWEEN 18 AND 25 PERCENT. ALTHOUGH S/SWLY LOW-LEVEL
WINDS WILL STRENGTHEN...THIS REGION OF LOW RH VALUES SHOULD REMAIN
TO THE E/SE OF STRONGER LOW-LEVEL FLOW CENTERED OVER THE MID-MO
VALLEY. SUSTAINED SURFACE WINDS SHOULD BECOME MODERATE /NEAR 15
MPH/...WITH GUSTS TO AROUND 25 MPH.

...NRN SACRAMENTO VALLEY OF NRN CA...
RECENT MESONET OBSERVATIONS CONFIRM AREAS OF GUSTY NLY WINDS /AROUND
2O TO 30 MPH/ OCCURRING ACROSS THE NRN SACRAMENTO VALLEY AND
SURROUNDING FOOTHILLS. THIS HAS SUPPORTED POOR OVERNIGHT RH
RECOVERY...WITH 12 TO 20 PERCENT READINGS COMMON AS OF 07Z. AS THE
TIGHT LOW-LEVEL PRESSURE GRADIENT RELAXES WITH THE RIDGE AXIS OVER
THE PACIFIC NW WEAKENING...WINDS WILL GRADUALLY DIMINISH DURING THE
LATE MORNING/EARLY AFTERNOON AND SHOULD REMAIN WEAK THROUGH THE REST
OF THE PERIOD. NEVERTHELESS...LONG DURATIONS OF LOW RH APPEAR LIKELY
WITH MIN VALUES NEAR 5 PERCENT AT PEAK HEATING.

..GRAMS.. 09/06/2010

...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...

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SPC Day 2 Fire Weather Outlook

DAY 2 FIRE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0456 AM CDT MON SEP 06 2010

VALID 071200Z - 081200Z

...NO CRITICAL AREAS...

...SYNOPSIS...
POTENT UPPER-LEVEL SHORT WAVE TROUGH OVER THE UPPER MS VALLEY WILL
TRANSLATE EWD ACROSS THE GREAT LAKES/SRN ONTARIO THROUGH EARLY WED.
ATTENDANT SURFACE COLD FRONT WILL MARCH EWD ACROSS THE UPPER GREAT
LAKES AND MIDWEST BY TUE AFTERNOON. IN THE WEST...A LARGE-SCALE
UPPER-LEVEL TROUGH WILL BECOME ANCHORED ACROSS THE PACIFIC NW INTO
NRN CA.

...PORTIONS OF CNTRL/ERN NV...
LATEST MODEL FORECASTS ARE FAIRLY CONSISTENT WITH THE DEPICTION OF A
WEAK MID-LEVEL IMPULSE EJECTING OUT AHEAD OF A LARGE-SCALE TROUGH
AMPLIFYING OVER THE PACIFIC NW. ASSOCIATED SPEED MAX WILL AID IN
STRENGTHENING BOUNDARY LAYER FLOW TUE AFTERNOON. HOWEVER...MODEL
FORECASTS DIFFER WITH THE AMPLITUDE OF THIS STRENGTHENING. 06Z NAM
AND ASSOCIATED WRF MEMBERS IN THE 03Z SREF APPEAR STRONGER THAN 00Z
GFS/ECMWF GUIDANCE. IN ADDITION...BOTH THE GFS/ECMWF INDICATE MORE
ROBUST SUB-TROPICAL MOISTURE EMANATING NWD FROM NWRN
MEXICO/AZ...SUGGESTING THE JUXTAPOSITION OF STRONG WINDS/LOW RH
WOULD BE NARROW BOTH SPATIALLY AND TEMPORALLY. AS SUCH...CONFIDENCE
IS LOWER THAN AVERAGE FOR DELINEATING A CRITICAL AREA ATTM.

...NRN SIERRA MTNS OF NERN CA/NWRN NV...
LOW/MID-LEVEL SWLYS WILL STRENGTHEN WITH APPROACH OF AN UPPER-LEVEL
TROUGH DIGGING ACROSS THE PACIFIC NW. HOWEVER...MODEL FORECASTS
DIFFER WITH THE AMPLITUDE OF THIS STRENGTHENING DURING THE DIURNAL
HEATING CYCLE...WITH THE NAM/WRF-BASED SREF MEMBERS STRONGER THAN
THE GFS/ECMWF. CONSENSUS OF MODEL GUIDANCE SUGGESTS THE STRONGEST
FLOW WILL DEVELOP DURING THE EARLY EVENING WHICH MAY MARGINALIZE THE
DURATION OF POTENTIALLY STRONG WINDS OVERLAPPING WITH LOW RH.
PREDICTABILITY REMAINS TOO LOW TO CONFIDENTLY DELINEATE A CRITICAL
AREA ATTM.

...SRN LOWER MI...
A SHORT-DURATION PERIOD OF CRITICAL CONDITIONS MAY DEVELOP DURING
MID AFTERNOON ON TUE. CONSENSUS OF MODEL GUIDANCE INDICATES
SUBSTANTIAL LOWER-TROPOSPHERIC DRYING WILL OCCUR AS A MID-LEVEL DRY
SLOT OVERSPREADS THE UPPER GREAT LAKES AND A SURFACE COLD FRONT
PUSHES EWD TOWARDS THE LOWER GREAT LAKES. RH VALUES SHOULD BECOME
MARGINALLY LOW FOR A FEW HOURS /FROM 25 TO 35 PERCENT/ UNTIL MORE
PRONOUNCED COOLING OCCURS LATE IN THE DAY. WITH 40 TO 50 MPH
LOW-LEVEL FLOW...SUSTAINED SURFACE WINDS OF 25 TO 30 MPH APPEAR
LIKELY. RAINFALL DURING THE PAST WEEK AND THE SHORT DURATION OF
MARGINALLY LOW RH SHOULD HELP MITIGATE THE OVERALL THREAT.

...PORTIONS OF THE ALLEGHENY PLATEAU IN SERN OH...WRN WV/PA...
MARGINAL FIRE WEATHER CONDITIONS SHOULD DEVELOP TUE AFTERNOON AS A
RELATIVELY WARM/DRY AIR MASS REMAINS WITHIN A NARROW SW TO NE
CORRIDOR DOWNSTREAM OF AN APPROACHING COLD FRONT. AS SWLY LOW-LEVEL
FLOW INCREASES...SUSTAINED SURFACE WINDS SHOULD BECOME MODERATE
/NEAR 15 MPH/. ABOVE-NORMAL TEMPERATURES IN THE MIDDLE 80S TO LOWER
90S WILL SUPPORT RH VALUES BECOMING MARGINALLY LOW /AROUND 25 TO 30
PERCENT/. GIVEN BELOW-NORMAL RAINFALL ACROSS THE REGION DURING THE
PAST FEW WEEKS...AN ENHANCED FIRE WEATHER THREAT APPEARS PROBABLE.

..GRAMS.. 09/06/2010

...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...

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