561
FXUS21 KWNC 221914
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT JULY 22 2026
SYNOPSIS: PERSISTENT MID-LEVEL HIGH PRESSURE IS EXPECTED TO BRING AN ELEVATED
RISK OF EXTREME HEAT TO A LARGE PORTION OF THE CENTRAL AND WESTERN CONTIGUOUS
U.S. (CONUS) WITH HEAT LINGERING ACROSS PARTS OF THE SOUTHEAST. HOT WEATHER AND
NEAR OR BELOW NORMAL RAINFALL BRING AN INCREASED RISK OF RAPID ONSET DROUGHT TO
PART OF THE NORTHERN GREAT PLAINS. IN THE WEST, THE MONSOONAL CIRCULATION MAY
BE PERIODICALLY ROBUST BUT THE OVERALL PATTERN IS NOT FAVORABLE FOR WIDESPREAD
HEAVY PRECIPITATION. ADDITIONALLY, ENHANCED MOIST FLOW ASSOCIATED WITH THE
MONSOON AND TROPICAL CYCLONES IN THE EAST PACIFIC WEST OF MEXICO MAY INCREASE
HUMIDITY AND RESULTING INCREASED HEAT INDEX VALUES ACROSS PARTS OF THE WEST.
ONE OR MORE TROPICAL CYCLONES MIGHT ALSO IMPACT HAWAII, RAISING THE POTENTIAL
FOR HEAVY PRECIPITATION AND GUSTY WINDS. MEANWHILE, A POSSIBLE SURFACE LOW
TRACKING ACROSS THE EASTERN U.S./CANADIAN BORDER AND ASSOCIATED WAVERING
FRONTAL BOUNDARY ACROSS THE SOUTHEASTERN CONUS AND SOUTHERN MID-ATLANTIC
SUPPORTS A SLIGHT RISK OF HEAVY PRECIPITATION FOR THESE REGIONS UNTIL THE
BEGINNING OF AUGUST.
HAZARDS
HIGH RISK OF EXTREME HEAT FOR PORTIONS OF THE SOUTHERN PLAINS, LOWER
MISSISSIPPI VALLEY, SOUTHWEST, GREAT BASIN, AND CALIFORNIA VALLEYS, THU-FRI,
JUL 30-31.
MODERATE RISK OF EXTREME HEAT FOR MUCH OF THE SOUTHERN AND CENTRAL PLAINS,
LOWER MISSISSIPPI VALLEY, ROCKIES, GREAT BASIN, CALIFORNIA, AND THE SOUTHWEST,
THU-SAT, JUL 30-AUG 1.
SLIGHT RISK OF EXTREME HEAT FOR MANY PARTS OF THE WESTERN TWO-THIRDS OF THE
CONUS AND SOUTHEAST U.S., THU-WED, JUL 30-AUG 5.
SLIGHT RISK OF EXTREME HEAT FOR PARTS OF THE NORTHERN PLAINS SOUTHWESTERN UPPER
MISSISSIPPI VALLEY, THU-FRI, JUL 30-31.
SLIGHT RISK OF HEAVY PRECIPITATION FOR THE CENTRAL GULF COAST, PART OF THE
SOUTH ATLANTIC REGION, AND THE EASTERN CAROLINAS, THU-SUN, JUL 30-AUG 2.
RAPID ONSET DROUGHT (ROD) POSSIBLE FOR PART OF THE NORTHERN GREAT PLAINS.
DETAILED SUMMARY
FOR SATURDAY JULY 25 - WEDNESDAY JULY 29:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR THURSDAY JULY 30 - WEDNESDAY AUGUST 05: MODELS CONTINUE TO BE IN GOOD
AGREEMENT FEATURING A PERSISTENT AMPLIFIED 500-HPA RIDGING OVER THE WESTERN AND
CENTRAL CONUS, SHIFTING WESTWARD WITH TIME AND TROUGHING ACROSS THE
NORTHEASTERN REGION AND MID-ATLANTIC. THE CENTER PEAK OF MID-LEVEL HIGH
PRESSURE MAY REACH 597 DM OVER THE FOUR CORNERS REGION, EARLY IN THE PERIOD
(JULY 30-31). THERE ARE SOME DIFFERENCES AMONG MODELS REGARDING THE DETAILS OF
THIS FEATURE, WITH THE GEFS FAVORING THE AXIS OF THIS RIDGE CENTERED NEAR THE
NORTHERN PLAINS, BUT THE ECENS FAVORING IT FURTHER WEST ACROSS THE NORTHERN
GREAT BASIN. THIS FEATURE FAVORS AN INCREASED RISK OF EXTREME HEAT ACROSS LARGE
PARTS OF THE WESTERN AND CENTRAL CONUS WITH HEAT LINGERING ACROSS THE
SOUTHEASTERN PORTION.
HIGHER THAN NORMAL DEWPOINTS FAVORED EAST OF THE ROCKIES DUE TO A LONG FETCH OF
GULF MOISTURE NEAR THE SURFACE, INCREASING DEW POINTS AND HELPING TO DRIVE UP
HEAT INDEX VALUES ACROSS SOME PARTS OF THE EAST-CENTRAL CONUS AND SOUTHEAST. A
HIGH RISK (>60% CHANCE) OF EXTREME HEAT HAS BEEN DESIGNATED ACROSS PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, SOUTHWEST, GREAT BASIN, AND
CALIFORNIA VALLEYS JUL 30-31, WHERE AND WHEN THERE ARE SIGNIFICANT CHANCES IN
HEAT TOOLS AND PETS FOR EXTREME HEAT. A MODERATE RISK (40-60% CHANCE) IS POSTED
FOR JUL 30-AUG 1 FOR MUCH OF THE SOUTHERN AND CENTRAL PLAINS, LOWER MISSISSIPPI
VALLEY, ROCKIES, GREAT BASIN, CALIFORNIA, AND THE SOUTHWEST. A BROAD
SURROUNDING AREA IS HIGHLIGHTED WITH A SLIGHT RISK, THROUGHOUT WEEK-2, FOR MANY
PARTS OF THE WESTERN TWO-THIRDS OF THE CONUS AND SOUTHEAST U.S. AN AREA OF
SLIGHT RISK IS DESIGNATED FOR PARTS OF THE NORTHERN PLAINS SOUTHWESTERN UPPER
MISSISSIPPI VALLEY, JUL 30-31 BEFORE THE RIDGE SHIFTS WESTWARD. ADDITIONALLY,
ENHANCED MOISTURE FROM THE SOUTHWEST MONSOON AND POSSIBLE TROPICAL CYCLONES
WEST OF MEXICO MAY BRING INCREASED HUMIDITY TO PARTS OF THE WEST THAT COULD
INCREASE HEAT INDEX VALUES. ANOMALOUSLY HIGH SSTS IN THE WATERS ADJACENT TO
THE GULF AND SOUTH ATLANTIC COASTS ARE EXPECTED TO CONTRIBUTE TO HEAT AND
HUMIDITY EAST OF THE ROCKIES. ABSOLUTE TEMPERATURES OR HEAT INDEX VALUES MAY
REACH 105 DEG F ACROSS PARTS OF THE CALIFORNIA CENTRAL VALLEY, GULF COAST, AND
FLORIDA, 105 TO 110 DEG F ACROSS THE GREAT PLAINS AND LOWER MISSISSIPPI VALLEY,
AND 115 DEG F ACROSS THE DESERT SOUTHWEST. ACCORDING TO THE NATIONAL BLEND OF
MODELS (NBM), THE SOUTHERN TIER MAY EXPERIENCE NEAR OR RECORD BREAKING HIGH
NIGHTTIME TEMPERATURES IN THE UPPER 70S TO LOW 80S, WHICH WOULD PROVIDE LITTLE
OVERNIGHT RELIEF.
SURFACE LOWS ARE POSSIBLE ACROSS THE INTERIOR WEST DURING WEEK-2, WHICH COULD
SUPPORT PERIODS OF GUSTY CONDITIONS. THERE IS INSUFFICIENT CERTAINTY REGARDING
THE SPECIFICS OF HIGH WINDS TO DESIGNATE A HIGH WIND HAZARD. REGARDLESS, THE
COMBINATION OF HOT TEMPERATURES, DRY CONDITIONS, AND WIND GUSTS COULD LEAD TO
ENHANCED WILDFIRE RISK ACROSS THE WEST, ESPECIALLY ACROSS AREAS ALREADY
EXPERIENCING ACTIVE WILDFIRES.
ANTECEDENT DRYNESS, ANOMALOUS WARMTH AND DRYNESS DURING WEEK-1, AND THE
POTENTIAL FOR EXTREME HEAT DURING WEEK-2 SUPPORT AN ENHANCED RISK OF RAPID
ONSET DROUGHT (ROD) ACROSS PORTIONS OF THE NORTHERN PLAINS. THE ANTICIPATED
HEAT IS EXPECTED TO OVERWHELM ANY SHORT-LIVED RELIEF THAT MAY OCCUR.
WEEK-2 IS EXPECTED TO BE AN ACTIVE PERIOD OF TROPICAL ACTIVITY IN THE EASTERN
PACIFIC. MORE THAN ONE TROPICAL CYCLONE IS EXPECTED, AND MODELS HAVE
CONSISTENTLY SHOWN AT LEAST ONE OF THESE SYSTEMS MOVING FAR ENOUGH TOWARD THE
CENTRAL PACIFIC TO THREATEN HAWAII WITH HEAVY RAIN AND HIGH WINDS. PLEASE REFER
TO THE NATIONAL HURRICANE CENTER (NHC) FOR THE LATEST TROPICAL DEVELOPMENTS.
DESPITE THE STRONG MID-LEVEL RIDGE FAVORED ACROSS THE WESTERN CONUS, THE
FORECAST POSITION OF THE RIDGE CENTER DOES NOT SUPPORT AN EXTREME ADVECTION OF
MONSOONAL MOISTURE INTO THE REGION TO SUPPORT WIDESPREAD HEAVY PRECIPITATION,
ALTHOUGH LOCALIZED HEAVY PRECIPITATION DUE TO POSSIBLE SURGES IN TROPICAL
MOISTURE ASSOCIATED WITH ONE OR MORE OF THE TROPICAL CYCLONES IN THE EASTERN
PACIFIC TRACKING NORTHWARD.
MULTIPLE MODELS INDICATE A SURFACE LOW TRACKING ALONG THE EASTERN U.S./CANADIAN
BORDER AT THE BEGINNING OF WEEK-2, WITH AN ASSOCIATED WAVERING FRONTAL BOUNDARY
NEAR THE CENTRAL GULF AND SOUTH ATLANTIC COASTAL REGIONS IN CONJUNCTION WITH
THE MID-LEVEL TROUGHING FAVORED OVER THE EASTERN U.S. THIS PATTERN SUPPORTS
SLIGHT RISK OF HEAVY PRECIPITATION TO PARTS OF THE CENTRAL GULF COAST, SOUTH
ATLANTIC REGION, AND EASTERN CAROLINAS, JUL 29-AUG 1. THERE IS UNCERTAINTY
ABOUT HOW MUCH RAINFALL OCCURS OVER THE LAND VERSUS OFFSHORE, THUS ONLY A
SLIGHT RISK IS DESIGNATED. THE GEFS AND ECENS PETS INDICATE AT LEAST A 20%
CHANCE OF 3-DAY RAINFALL EXCEEDING THE 85TH PERCENTILE CLIMATOLOGICALLY AND ONE
INCH.
FORECASTER: MELISSA OU
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