836
FNUS22 KWNS 191958
FWDDY2
DAY 2 FIRE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT THU JUN 19 2025
VALID 201200Z - 211200Z
...CRITICAL FIRE WEATHER AREA FOR MUCH OF THE GREAT BASIN INTO THE
SOUTHWEST...
..GREAT BASIN INTO THE SOUTHWEST
A PROMINENT LOW PRESSURE SYSTEM AND ASSOCIATED 60-70 MPH MID-LEVEL
JET ENTERING THE NORTHWESTERN U.S. WILL PROMOTE AN EXPANSIVE AREA OF
CRITICAL FIRE WEATHER CONDITIONS ACROSS MUCH OF THE GREAT BASIN,
NORTHERN ARIZONA AND FOUR CORNERS AREA ON FRIDAY. THE PRONOUNCED
JUXTAPOSITION OF A MID-LEVEL JET MAXIMA, A DEEP AND WELL-MIXED
BOUNDARY LAYER AND SURFACE RELATIVE HUMIDITY OF 10 PERCENT OR BELOW
IS EXPECTED ACROSS EASTERN UTAH AND WESTERN COLORADO. THE
COMBINATION OF SUSTAINED WINDS OF 25-30 MPH AND VERY DRY SURFACE
LAYER COULD YIELD LOCALLY EXTREMELY CRITICAL FIRE WEATHER CONDITIONS
ACROSS WESTERN PORTIONS OF THE COLORADO PLATEAU FRIDAY.
..SOUTHERN CALIFORNIA INTO THE SAN JOAQUIN VALLEY
ENHANCED WEST-NORTHWEST FLOW AND WITHIN A DRY BOUNDARY LAYER WILL
SUPPORT AN ELEVATED FIRE WEATHER THREAT MAINLY LEEWARD OF INTERIOR
MOUNTAIN RANGES ACROSS SOUTHERN CALIFORNIA FRIDAY. PREVIOUS FORECAST
(SEE BELOW) REMAINS ON TRACK.
..WILLIAMS.. 06/19/2025
PREV DISCUSSION
/ISSUED 0209 AM CDT THU JUN 19 2025/
..SYNOPSIS
A ROBUST MIDLEVEL LOW WILL ADVANCE EASTWARD ACROSS THE NORTHWEST
DURING THE DAY, WHILE A SWATH OF STRONG DEEP-LAYER WESTERLY FLOW
OVERSPREADS MUCH OF THE WESTERN CONUS. IN RESPONSE, SURFACE LOW
PRESSURE WILL DEEPEN OVER THE NORTHERN GREAT BASIN, PROMOTING A
TIGHTENING PRESSURE GRADIENT ACROSS THE GREAT BASIN INTO THE
SOUTHWEST. THIS LARGE-SCALE PATTERN WILL SUPPORT WIDESPREAD CRITICAL
FIRE-WEATHER CONDITIONS ACROSS THE GREAT BASIN INTO THE SOUTHWEST.
..GREAT BASIN INTO THE SOUTHWEST
STRONG DIURNAL HEATING AMID A DRY ANTECEDENT AIR MASS WILL SUPPORT
ANOTHER DAY OF WIDESPREAD SINGLE-DIGIT RH ACROSS THE REGION. AT THE
SAME TIME, DEEP BOUNDARY-LAYER MIXING INTO THE STRONG FLOW ALOFT,
COMBINED WITH THE TIGHTENING PRESSURE GRADIENT, WILL YIELD AN
EXPANSIVE AREA OF 20-30 MPH SUSTAINED SOUTHWESTERLY SURFACE WINDS.
GIVEN INCREASINGLY DRY FUELS ACROSS MUCH OF THE GREAT BASIN INTO THE
SOUTHWEST, WIDESPREAD CRITICAL FIRE-WEATHER CONDITIONS ARE EXPECTED,
WITH LOCALIZED EXTREMELY CRITICAL CONDITIONS POSSIBLE OVER
TERRAIN-FAVORED AREAS.
..SOUTHERN CA INTO THE SAN JOAQUIN VALLEY
DEEP-LAYER WEST-NORTHWESTERLY FLOW ON THE UPSTREAM-SIDE OF THE
MIDLEVEL LOW WILL OVERSPREAD CENTRAL AND SOUTHERN CA, WHERE THE
TIGHT REGIONAL PRESSURE GRADIENT WILL BE IN PLACE. THIS WILL PROMOTE
BREEZY/GUSTY SURFACE WINDS PRIMARILY OVER THE INTERIOR MOUNTAINS AND
VALLEY -- WHERE 15-20 PERCENT RH IS EXPECTED. THESE DRY/BREEZY
CONDITIONS WILL FAVOR ELEVATED FIRE-WEATHER CONDITIONS WHERE FUELS
ARE RECEPTIVE TO WILDFIRE SPREAD.
..PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT
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