066
FNUS22 KWNS 241828
FWDDY2
DAY 2 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0127 PM CDT FRI MAY 24 2013
VALID 251200Z - 261200Z
..CRITICAL FIRE WEATHER AREA FOR FAR SRN NV...EXTREME SRN UT
NRN
AZ...PORTIONS OF NWRN/W-CNTRL NM...SWRN CO...
..FAR SRN NV...EXTREME SRN UT...NRN AZ
PORTIONS OF NWRN/W-CNTRL
NM...SWRN CO...
NO CHANGES HAVE BEEN MADE TO THE ONGOING FORECAST. THE LATEST
MULTI-MODEL CONSENSUS INDICATES THAT CRITICAL FIRE WEATHER
CONDITIONS ARE ANTICIPATED AS AFTERNOON RH VALUES OF 8-14 PERCENT
COMBINE WITH SSWLY/SWLY SFC WINDS AROUND 20-25 MPH AND GUSTS
REACHING AROUND 30 MPH.
..SRN AZ
NO CHANGES HAVE BEEN MADE TO THE ONGOING FORECAST. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED AS RH VALUES BECOME CRITICALLY LOW.
HOWEVER...IN THE ABSENCE OF STRONGER LOW/MID-LEVEL FLOW...CRITICALLY
STRONG SUSTAINED WIND SPEEDS ARE NOT EXPECTED TO OCCUR ON ANY MORE
THAN A BRIEF/SPOTTY BASIS. AS SUCH...CRITICAL DESIGNATION IS NOT
NEEDED.
..MOUNTAINS OF CNTRL NM AND THE IMMEDIATELY ADJACENT HIGH PLAINS
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP
DURING THE AFTERNOON HOURS OVER THE CNTRL NM MOUNTAINS AS OROGRAPHIC
ASCENT STRENGTHENS. PW VALUES FROM 0.50 TO 0.75 INCH AND DEEP
INVERTED-VEE THERMODYNAMIC PROFILES PER FORECAST SOUNDINGS SHOULD
SUPPORT A DRY-THUNDERSTORM MODE. AND...WITH DRY/VERY DRY
FUELS...LIGHTNING-INDUCED IGNITIONS COULD OCCUR AS SFC RH VALUES
FALL TO AROUND 15-20 PERCENT AMIDST DRY/VERY DRY FUELS.
AS THUNDERSTORMS ADVANCE OVER THE LOWER ELEVATIONS OF ERN NM AND
ENCOUNTER RICHER LOW-LEVEL MOISTURE/GREATER BUOYANCY...
EVOLVING/MERGING COLD POOLS MAY YIELD SOMEWHAT HIGHER THUNDERSTORM
COVERAGE. HOWEVER...THIS ACTIVITY WILL ENCOUNTER INCREASINGLY HIGHER
PW/HIGHER SFC RH...WITH THE THUNDERSTORM MODE TRANSITIONING TO MIXED
WET/DRY. REGARDLESS...LIGHTNING STRIKES OUTSIDE OF RAIN CORES COULD
YIELD IGNITIONS AMIDST ONGOING DROUGHT CONDITIONS.
SINCE THE COVERAGE OF PURELY DRY THUNDERSTORMS IS NOT EXPECTED TO
EXCEED WIDELY SCATTERED...A DRY-THUNDERSTORM CRITICAL AREA HAS NOT
BEEN INCLUDED AT THIS TIME.
..COHEN.. 05/24/2013
PREV DISCUSSION
/ISSUED 0458 AM CDT FRI MAY 24 2013/
..SYNOPSIS
AN UPPER LOW IS FORECAST TO REMAIN NEARLY STATIONARY ACROSS THE
PACIFIC NORTHWEST AS A SERIES OF SUBTLE SHORTWAVE TROUGHS ROTATES
THROUGH THE LARGER SCALE FLOW AROUND THIS LOW ON SATURDAY.
ACROSS THE SOUTHWESTERN STATES...A ZONE OF ENHANCED WEST/SOUTHWEST
FLOW IS EXPECTED TO PERSIST THROUGH SATURDAY. HERE /ONCE AGAIN/
STRONG INSOLATION SHOULD RESULT IN DEEP MIXING OF A PERSISTENTLY DRY
BOUNDARY LAYER...RESULTING IN WARM DAYTIME TEMPERATURES /80S AND
90S/ AND LOW AND RELATIVE HUMIDITY VALUES IN THE SINGLE DIGITS TO
LOW TEENS FOR MUCH OF THE DAY. ADDITIONALLY...GIVEN THE RELATIVELY
STRONG FLOW ALOFT AND THE FORECAST DEEP MIXING...STRONG/GUSTY SFC
WINDS /20-25 MPH WITH GUSTS TO 30/ SHOULD DEVELOP...WARRANTING THE
CRITICAL RISK.
..SOUTHERN ARIZONA
CONDITIONS HERE APPEAR TO BE SIMILAR TO THOSE FARTHER NORTH IN THE
CRITICAL AREA. ONE MITIGATING FACTOR IN THIS AREA IS THAT IT THIS
AREA IS A LITTLE MORE REMOVED FROM THE STRONG MID-LEVEL FLOW AND
THUS AFTERNOON MIXING SHOULD RESULT IN SLIGHTLY WEAKER SFC WINDS
NEARING...BUT NOT ACHIEVING...CRITICAL THRESHOLDS FOR THE REQUISITE
DURATION /3 HRS/.
..PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT
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