Storm Prediction Center Day 1 Fire Weather Outlook
Created: Tue Jun 17 16:50:04 UTC 2014 (
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Storm Prediction Center Day 1 Fire Weather Outlook
Created: Tue Jun 17 16:50:04 UTC 2014 (
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Click for Day 1 FireWX Areal Outline Product
ZCZC SPCFWDDY1 ALL
FNUS21 KWNS 171648
DAY 1 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1148 AM CDT TUE JUN 17 2014
VALID 171700Z - 181200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF NRN AZ...SRN
UT...NWRN NM...FAR SWRN CO...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF AZ...SERN CA...SRN/ERN
UT...WRN CO...CNTRL/NRN NM...FAR SRN NV SURROUNDING THE EXTREMELY
CRITICAL AREA...
...PRIMARY CHANGES TO THE DAY-1 FIRE WEATHER OUTLOOK...
/1/ THE EXTREMELY CRITICAL AREA HAS BEEN EXPANDED SWWD...SWD...AND
EWD UPON COORDINATION WITH THE FLAGSTAFF...LAS VEGAS...AND
ALBUQUERQUE WEATHER FORECAST OFFICES. THE FLAGSTAFF OBSERVED
SOUNDINGS HAVE SAMPLED EVEN STRONGER FLOW ALOFT THIS MORNING
COMPARED TO YESTERDAY MORNING...WITH AOA 45 MPH OF FLOW EXTENDING AS
LOW AS 3 KFT ABOVE GROUND AND 55-65 MPH OF FLOW ABOVE THE 700-MB
LEVEL TO 600 MB THIS MORNING. THIS IS IN ASSOCIATION WITH A
MID-LEVEL WIND-SPEED MAXIMUM...WHICH THE LATEST SHORT-RANGE MODEL
GUIDANCE DEPICTS AS OVERLYING THE REGION THROUGH THE DAY. CONFIDENCE
HAS INCREASED IN A GREATER-COVERAGE REGION WHERE THIS SPEED MAX WILL
SUPPORT SFC WINDS OF 30-40 MPH WITH GUSTS REACHING 45-55 MPH ACROSS
PORTIONS OF THE COLORADO PLATEAU...AS A DEEP CYCLONE REMAINS N OF
THE REGION.
FURTHERMORE...WITH RICHER SUBTROPICAL MOISTURE ALOFT PRIMARILY
RELEGATED TO SRN AZ INTO CNTRL/SRN NM...GPS DATA AND THE MORNING
SOUNDING FROM FLAGSTAFF INDICATE 0.25-0.40-INCH PW ACROSS A BROAD
PORTION OF NRN AZ INTO THE CNTRL GREAT BASIN. DIURNALLY DEEPENING
VERTICAL MIXING AMIDST DOWNSLOPE-ENHANCED WARMING/DRYING WILL
SUPPORT RH VALUES FALLING TO 8-10 PERCENT IN MANY AREAS -- I.E.
SLIGHTLY HIGHER THAN THOSE VALUES YESTERDAY -- IN COLLOCATION WITH
VERY STRONG WINDS AND VERY DRY FUELS. AS SUCH...THE EXPANSION TO THE
EXTREMELY CRITICAL AREA IS WARRANTED. SFC OBSERVATIONS INDICATE
CRITICAL CONDITIONS ALREADY ONGOING IN SOME AREAS...AND ADDITIONAL
INCREASES IN WIND SPEEDS AND REDUCTIONS IN SFC RH WILL OCCUR. EVEN
IF RH VALUES FAIL TO FALL TO 10 PERCENT IN SOME LOCATIONS...WHICH
MAY BECOME A CONCERN AT HIGHER ELEVATIONS...THE STRENGTH OF THE
AFOREMENTIONED WINDS AMIDST SUFFICIENTLY LOW RH AND VERY DRY FUELS
WARRANTS THE EXTREMELY CRITICAL DESIGNATION. ANY ONGOING FIRES WILL
HAVE THE POTENTIAL TO SPREAD VERY RAPIDLY.
/2/ THE CRITICAL AREA HAS BEEN EXPANDED EWD INTO PORTIONS OF
NRN/CNTRL NM UPON COORDINATION WITH THE ALBUQUERQUE WEATHER FORECAST
OFFICE. IN ASSOCIATION WITH THE AFOREMENTIONED WIND-SPEED MAXIMUM
ALOFT...THE MORNING OBSERVED SOUNDING AT ALBUQUERQUE SAMPLED 25-35
MPH OF WSWLY FLOW EXTENDING THROUGH A DEEP LAYER AND AS LOW AS 1.5
KFT ABOVE GROUND. STRENGTHENING VERTICAL MIXING WILL FOSTER STRONG
WSWLY SFC WINDS -- I.E. AROUND 20-25 MPH WITH HIGHER GUSTS -- AS RH
VALUES FALL TO 12-15 PERCENT. MODESTLY ENHANCED MID-LEVEL MOISTURE
MAY PREVENT STRONGER RH REDUCTIONS FROM OCCURRING. HOWEVER...WITH
MANY LOCATIONS ALREADY EXPERIENCING RH VALUES IN THE UPPER TEENS TO
THE LOWER 20S AS OF 16Z...CONFIDENCE IN RH VALUES BECOMING CRITICAL
FOR AT LEAST A FEW HOURS IS HIGHER WITHIN THE ADDED AREAS...AND
AFFIRMED BY SOME OF THE LATEST SHORT-RANGE MODEL GUIDANCE. GREEN-UP
OF FUELS IN NERN NM PRECLUDES CRITICAL DESIGNATION THERE...DESPITE
THE POSSIBILITY OF METEOROLOGICALLY CRITICAL FIRE WEATHER
CONDITIONS.
/3/ THE CRITICAL AREA HAS BEEN EXPANDED NWD INTO MORE OF WRN CO UPON
COORDINATION WITH THE GRAND JUNCTION WEATHER FORECAST OFFICE. THE
CONSENSUS AMONGST SHORT-RANGE DETERMINISTIC AND ENSEMBLE MODEL
GUIDANCE SUGGESTS THAT CRITICAL METEOROLOGICAL CONDITIONS WILL
EXTEND NEWD ACROSS PORTIONS OF THE CNTRL GREAT BASIN IN ASSOCIATION
WITH THE MID-LEVEL WIND-SPEED MAXIMUM. AT THE SAME TIME...THE
COORDINATION WITH THE GRAND JUNCTION OFFICE SUGGESTS THAT FUELS ARE
SUFFICIENTLY DRY INTO PORTIONS OF WRN CO TO WARRANT THE NWD
EXPANSION OF THE CRITICAL AREA...WHERE PRECIPITATION DURING THE PAST
COUPLE OF WEEKS HAS BEEN LIMITED.
/4/ THE CRITICAL AREA HAS BEEN EXPANDED SWWD INTO THE LOWER CO RIVER
VALLEY UPON COORDINATION WITH THE LAS VEGAS AND PHOENIX WEATHER
FORECAST OFFICES. WITH ENHANCED FLOW ALOFT TRAILING SWWD OVER DRY
SFC CONDITIONS PER THE LATEST MULTI-MODEL CONSENSUS...CRITICAL FIRE
WEATHER CONDITIONS ARE EXPECTED TO EXTEND FARTHER TO THE SW. AREAS
ADDED TO CRITICAL DESIGNATION ARE EXPECTED TO EXPERIENCE SWLY SFC
WINDS OF 20-25 MPH WITH HIGHER GUSTS AMIDST 8-13-PERCENT RH VALUES
THIS AFTERNOON. WINDS HAVE ALREADY INCREASED TO 14-18 MPH ACROSS
PORTIONS OF THE LOWER CO RIVER VALLEY WITH RH VALUES OF 12-15
PERCENT...AND FURTHER DIURNAL INCREASES IN WIND SPEEDS AND
REDUCTIONS IN RH ARE ANTICIPATED AS VERTICAL MIXING STRENGTHENS.
..COHEN.. 06/17/2014
.PREV DISCUSSION... /ISSUED 0351 AM CDT TUE JUN 17 2014/
...SYNOPSIS...
WEST COAST TROUGH WILL REMAIN CENTERED OVER THE INTERMOUNTAIN WEST
THROUGH THE FORECAST PERIOD AS A STRONG SHORT-WAVE TROUGH PIVOTS
AROUND THE LARGER-SCALE TROUGH. DOWNSTREAM FROM THIS
TROUGH...SOUTHWEST FLOW WILL BE PRESENT ABOVE THE CENTRAL UNITED
STATES...WITH A TRANSITION TO A MORE ZONAL FLOW ACROSS THE
NORTHEAST.
AT THE SURFACE...ANOTHER DAY WITH LEE CYCLOGENESIS ACROSS THE HIGH
PLAINS OF EASTERN WYOMING AND EASTERN COLORADO. THIS WILL ACT TO
TIGHTEN THE SURFACE PRESSURE GRADIENT ACROSS THE CENTRAL AND
SOUTHWEST UNITED STATES. ACROSS THE EAST...A FAST MOVING LOW
PRESSURE WILL TRAVERSE THE NORTHEAST...WHILE THE SOUTHEAST WILL
REMAIN UNDER THE INFLUENCE OF AN EXPANSIVE HIGH PRESSURE.
...NORTHERN ARIZONA...SOUTHEASTERN UTAH...NORTHWESTERN NEW
MEXICO...AND SOUTHWESTERN COLORADO...
WITH THE MID-/UPPER-LOW STILL LOCATED ACROSS THE INTERMOUNTAIN WEST
AND A STRONG SHORT-WAVE TROUGH MOVING THROUGH THE GREAT
BASIN...ANOTHER DAY OF STRONG/GUSTY SURFACE WINDS /LOCALLY SUSTAINED
30-35 MPH/ AND LOW RELATIVE-HUMIDITY VALUES /10-15 PERCENT WITH
LOCALLY LOWER VALUES/ IS EXPECTED. AS SUCH...WIDESPREAD CRITICAL
FIRE-WEATHER CONDITIONS ARE EXPECTED.
WITHIN THE LARGER CRITICAL AREA IT APPEARS A CORRIDOR FROM
NORTH-CENTRAL ARIZONA INTO SOUTHEAST UTAH WILL HAVE THE GREATEST
CHANCE OF SUSTAINED SURFACE WINDS GREATER THAN 30 MPH AND
RELATIVE-HUMIDITY VALUES LESS THAN 10 PERCENT COINCIDENT FOR 3 OR
MORE HOURS. AS SUCH...HAVE MAINTAINED THE GOING EXTREMELY CRITICAL
RISK FOR THIS AREA.
...SURROUNDING THE CRITICAL RISK AREA...
HERE...SUSTAINED SURFACE WINDS SHOULD ACHIEVE 15-25 MPH THROUGHOUT
THE DAY. HOWEVER...MINIMUM RELATIVE-HUMIDITY VALUES SHOULD BE
SLIGHTLY HIGHER THAN ON MONDAY. THIS SHOULD PRECLUDE WIDESPREAD
CRITICAL FIRE-WEATHER CONDITIONS. HOWEVER...THE CURRENT FORECAST
COMBINATIONS OF RELATIVE HUMIDITY AND WIND SPEEDS WILL SUPPORT
ELEVATED TO LOCALLY CRITICAL FIRE-WEATHER CONDITIONS.
...HIGHER TERRAIN OF SOUTHEAST ARIZONA AND MUCH OF NEW MEXICO...
SATELLITE IMAGERY INDICATED SEVERAL AREAS OF DRY CONVECTION ON
MONDAY ACROSS PORTIONS OF THIS AREA...ALTHOUGH IT APPEARS NONE WERE
ABLE TO PRODUCE LIGHTNING BEFORE WEAKENING/DECAYING. THIS
AFTERNOON...MODEST INSTABILITY /MUCAPE VALUES AROUND 500 J/KG/ WILL
ONCE AGAIN BE PRESENT. ONE DIFFERENCE BETWEEN TODAY AND YESTERDAY IS
THAT THIS AREA WILL BE GLANCED BY THE ASCENT ASSOCIATED WITH THE
TROUGH MOVING THROUGH THE GREAT BASIN. THIS INCREASED ASCENT SHOULD
RESULT IN MORE WIDESPREAD ATTEMPTS AT CONVECTION THAN YESTERDAY.
GIVEN THE FORECAST INCREASE IN PRECIPITABLE WATER...AT LEAST SOME OF
THESE CONVECTIVE ATTEMPTS SHOULD ACHIEVE THE ABILITY TO PRODUCE
LIGHTING. FORECAST SOUNDINGS ACROSS THE AREA SUPPORT STORM MOTIONS
AROUND 20-30 MPH WHICH WOULD TEND TO FAVOR A DRY THUNDERSTORM
MODE...BUT ALSO INDICATED AFTERNOON PRECIPITABLE-WATER VALUES SHOULD
RANGE FROM AROUND 0.6 TO 0.9 INCHES WHICH WOULD SUPPORT THE
POTENTIAL FOR HYBRID WET/DRY THUNDERSTORMS. GIVEN THE LONG-TERM
DROUGHT ACROSS PORTIONS OF THIS AREA...AND RECEPTIVE FUELS...HAVE
MAINTAINED ISOLATED DRY THUNDERSTORM HIGHLIGHTS.
...PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT...