425
FXUS21 KWNC 111843
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT JULY 11 2026
SYNOPSIS: AN EVOLVING PATTERN OF MID-LEVEL HIGH PRESSURE IS EXPECTED TO BRING
AN INCREASED RISK OF EXTREME HEAT THROUGHOUT PARTS OF THE NORTHWESTERN AND
NORTHCENTRAL CONTIGUOUS U.S. (CONUS), AS WELL AS ACROSS PORTIONS OF THE GULF
COAST AND THE SOUTHEAST. MID-LEVEL LOW PRESSURE SETTLING IN OVER THE MIDWEST
IS EXPECTED TO BRING COOLING TEMPERATURES EARLY IN WEEK-2, HOWEVER SURFACE LOW
DEVELOPMENT INCREASES THE RISK OF HEAVY PRECIPITATION FOR PARTS OF THE EASTERN
CONUS. THE PREVAILING MID-LEVEL PATTERN FORECAST IS ALSO CONSISTENT WITH AN
ENHANCED MONSOONAL CIRCULATION, POTENTIALLY BRINGING ENHANCED MOISTURE AND
HEAVY PRECIPITATION INTO PARTS OF THE SOUTHWESTERN CONUS.
HAZARDS
MODERATE RISK OF EXTREME HEAT ACROSS THE NORTHERN AND CENTRAL PLAINS, ADJACENT
PARTS OF THE MISSISSIPPI VALLEY, ROCKIES AND NORTHERN GREAT BASIN, SUN-MON, JUL
19-20.
MODERATE RISK OF EXTREME HEAT ACROSS PORTIONS OF THE FLORIDA PENINSULA,
SUN-MON, JUL 19-20.
SLIGHT RISK OF EXTREME HEAT FOR MUCH OF THE WESTERN AND CENTRAL CONUS, AND THE
SOUTHERN TIER OF THE CONUS (EXCLUDING THE LOWER FOUR CORNERS AND SOUTHERN HIGH
PLAINS), SUN-SAT, JUL 19-25.
SLIGHT RISK OF HEAVY PRECIPITATION FOR PORTIONS OF THE EASTERN GREAT LAKES,
OHIO VALLEY, APPALACHIANS, SOUTHEAST, MID-ATLANTIC, AND THE NORTHEAST, SUN-MON,
JUL 19-20.
SLIGHT RISK OF HEAVY PRECIPITATION FOR MUCH OF THE FOUR CORNERS, SUN-THU, JUL
19-23.
RAPID ONSET DROUGHT RISK ACROSS THE NORTHERN PLAINS.
DETAILED SUMMARY
FOR TUESDAY JULY 14 - SATURDAY JULY 18:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR SUNDAY JULY 19 - SATURDAY JULY 25: FOLLOWING A VERY WARM SUMMERTIME PATTERN
CHARACTERIZED BY AMPLIFIED 500-HPA RIDGING THROUGHOUT MUCH OF THE CONUS DURING
WEEK-1, DYNAMICAL MODELS CONTINUE TO ADVERTISE BOTH A DEAMPLIFICATION AND
RETROGRESSION OF THE ANOMALOUS MID-LEVEL RIDGE FEATURES BY NEXT WEEKEND. MUCH
OF THIS PATTERN TRANSITION IS ASSOCIATED WITH THE DEVELOPMENT OF A MEAN
LONGWAVE TROUGH OVER EASTERN NORTH AMERICA, WHICH IS EXPECTED TO ERODE A LOBE
OF MID-LEVEL HIGH PRESSURE OVER THE MISSISSIPPI, TENNESSEE AND OHIO VALLEYS,
WHICH EXTENDS FROM THE MAIN ANOMALOUS RIDGE CENTER OVER THE NORTHERN HIGH
PLAINS. AS THIS OCCURS, THE NORTHERN PLAINS RIDGE IS FAVORED TO SHIFT WESTWARD
AND GRADUALLY WEAKEN, THOUGH THE PERSISTENCE OF POSITIVE HEIGHT DEPARTURES
LOOKS TO SUSTAIN AN INCREASED HEAT RISK OVER PORTIONS OF THE WESTERN AND
CENTRAL CONUS EARLY IN THE PERIOD. EVEN WITH MORE TROUGHING AND COOLER
TEMPERATURES FAVORED OVER THE EASTERN U.S. EARLY IN THE PERIOD, ENHANCED
SUBTROPICAL RIDGING OVER THE GULF OF AMERICA AND WESTERN ATLANTIC LOOKS TO
REMAIN A FACTOR IN OUTLOOK PERIOD. AS THE MID-LEVEL TROUGHING OVER THE EASTERN
CONUS BECOMES LESS AMPLIFIED LATER IN WEEK-2, MODELS ARE BEGINNING TO SIGNAL A
BRIDGING BETWEEN THE SUBTROPICAL AND NORTHERN PLAINS ANOMALOUS RIDGE FEATURES,
RESULTING IN AN EXPANSION OF POSITIVE MID-LEVEL HEIGHT DEPARTURES IN
STANDARDIZED SPACE THROUGHOUT MUCH OF THE INTERIOR WEST, GREAT PLAINS AND
MISSISSIPPI VALLEY. CAUTION IS EXERCISED GIVEN GENERAL FORECAST UNCERTAINTY AT
THIS LEAD, HOWEVER, SUCH A PATTERN TRANSITION WOULD LIKELY PROMOTE A RENEWED
THREAT OF EXTREME HEAT CONDITIONS OVER THE CENTRAL CONUS LATER IN THE PERIOD.
BASED ON THE LATEST RAW AND CALIBRATED TEMPERATURE TOOLS, A MODERATE RISK OF
EXTREME HEAT REMAINS POSTED OVER PARTS OF THE NORTHWESTERN AND NORTH-CENTRAL
CONUS IN PROXIMITY TO THE MAIN ANOMALOUS RIDGE CENTER FAVORED EARLY IN THE
PERIOD. DUE TO SUBTLE CHANGES IN THE LATEST ENSEMBLE GUIDANCE IN REGARDS TO
TIMING OF THE PATTERN TRANSITION NEXT WEEKEND, THE MODERATE RISK IS EXTENDED
THROUGH DAY 9 (JUL 20) AND IS SLIGHTLY EXPANDED SOUTHWARD IN THE GREAT PLAINS
AND EASTWARD INTO THE MISSISSIPPI VALLEY WHERE ANOMALOUS RIDGING IS FAVORED TO
LINGER BEFORE MORE TROUGHING MOVES IN. WITHIN THE MODERATE RISK AREA, THERE
REMAINS INCREASED CHANCES FOR HEAT INDEX VALUES EXCEEDING 100 (105) DEG F IN
THE NORTHERN (CENTRAL) PLAINS AND UPPER (MIDDLE) MISSISSIPPI VALLEY, WITH THE
UNCALIBRATED ECMWF AND GEFS SHOWING INCREASED CHANCES (>30%) FOR DOUBLE DIGIT
POSITIVE TEMPERATURE DEPARTURES, AND THE GEFS PROBABILISTIC EXTREMES TOOL (PET)
INDICATING SIMILAR CHANCES FOR DAYTIME TEMPERATURES EXCEEDING THE 85TH
CLIMATOLOGICAL PERCENTILE FOR THE FIRST FEW DAYS OF PERIOD. THE COMBINATION OF
ANOMALOUS WARMTH, NEAR TO BELOW NORMAL PRECIPITATION FAVORED DURING WEEK-2, AND
ANTECEDENT DRYNESS SUPPORTS AN ENHANCED RISK OF RAPID ONSET DROUGHT ACROSS
PORTIONS OF THE NORTHERN PLAINS. WITH ENHANCED SUBTROPICAL RIDGING REMAINING
ENTRENCHED OVER THE LOWER LATITUDES, A MODERATE RISK OF EXTREME HEAT ALSO
REMAINS POSTED OVER CENTRAL AND SOUTHERN FLORIDA (JUL 19-20) WHERE PETS
CONTINUE TO INDICATE ELEVATED CHANCES FOR MAXIMUM TEMPERATURES EXCEEDING THE
85TH PERCENTILE EARLY IN THE PERIOD AND THE NATIONAL BLEND OF MODELS (NBM)
HIGHLIGHTS SEVERAL LOCATIONS WITH DAYTIME HIGHS AND NIGHTTIME LOWS NEARING
AND/OR BREAKING DAILY RECORDS EARLY IN THE PERIOD. IN ADDITION, SEA SURFACE
TEMPERATURES IN THE GULF OF AMERICA CONTINUE TO RUN VERY WARM, WITH ANOMALIES
REGISTERING UPWARDS OF 2 DEGREES C MAINLY OVER THE EASTERN PORTION OF THE GULF
TO SUPPORT CONTINUED SURFACE WARMTH ALONG THE GULF STATES.
SURROUNDING THESE MODERATE RISK AREAS, A SLIGHT RISK OF EXTREME HEAT REMAINS
POSTED FOR MUCH OF THE WESTERN CONUS, EXCLUDING THE PARTS OF THE LOWER FOUR
CORNERS AND SOUTHERN HIGH PLAINS WHERE TEMPERATURE TOOLS CONTINUE TO INDICATE
COOLER TEMPERATURES ASSOCIATED WITH AN UPTICK IN MONSOONAL PRECIPITATION
(DISCUSSED BELOW). DUE TO THE AFOREMENTIONED POTENTIAL FOR THE RETURN OF RISING
MID-LEVEL HEIGHTS OVER THE CENTRAL CONUS LATER IN WEEK-2, THE SLIGHT RISK AREA
IS EXPANDED TO INCLUDE MORE OF THE SOUTHERN PLAINS AND THE MISSISSIPPI VALLEY,
AND IS MERGED WITH THE SLIGHT RISK AREA OF EXTREME HEAT PREVIOUSLY HIGHLIGHTED
OVER THE GULF STATES, VALID FOR ALL OF WEEK-2. THE SLIGHT RISK AREA ALSO NOW
INCLUDES PORTIONS OF THE SOUTHEAST BASED ON WARMING TRENDS IN THE RAW AND
CALIBRATED TEMPERATURE TOOLS. THIS BROAD ADJUSTMENT IS EXPECTED TO CAPTURE BOTH
THE PERSISTENT HEAT THREAT ACROSS THE GULF STATES AS WELL AS ANY REEMERGING
HEAT RISKS ASSOCIATED WITH THE REBUILDING RIDGE PATTERN, WHICH IS GENERALLY
SUPPORTED IN BOTH THE GEFS AND ECMWF PETS.
TIED TO THE TROUGHING FAVORED OVER THE EASTERN U.S. EARLY IN WEEK-2, ENSEMBLES
CONTINUE TO POINT TO SURFACE LOW DEVELOPMENT ALONG THE EASTERN SEABOARD.
RELATIVE TO YESTERDAY, A MORE NORTHERLY MEAN SOLUTION OF THE SURFACE LOW IS
FEATURED IN THE ECMWF, WHEREAS THE GEFS CONTINUES TO BE MORE TENUOUS WITH THIS
POTENTIAL WHICH IS BEST REFLECTED IN THE GEFS PET FAVORING LITTLE TO NO WET
SIGNAL IN PERCENTILE SPACE. HOWEVER, BOTH THE RAW GEFS AND ECMWF PROBABILITY
OF EXCEEDANCE TOOLS REMAIN SUPPORTIVE OF A HEAVY PRECIPITATION RISK, DEPICTING
20-40% CHANCES OF 3-DAY AMOUNTS EXCEEDING AN INCH, WITH MORE COVERAGE FEATURED
FURTHER NORTH AND WEST OVER THE EASTERN OHIO VALLEY AND THE NORTHEAST COMPARED
TO YESTERDAY. THEREFORE, A CORRESPONDING SLIGHT RISK AREA REMAINS POSTED IN
THE OUTLOOK (JUL 19-20) AND IS ADJUSTED ACCORDINGLY. ELEVATED WIND SPEEDS ARE
ALSO POSSIBLE WITHIN THE SLIGHT PRECIPITATION RISK AREA, THOUGH THERE REMAINS A
FAIR AMOUNT OF ENSEMBLE SPREAD IN REGARDS TO STRENGTH AND POSITION OF THE LOW
TO INDUCE HAZARDOUS WINDS ONSHORE, THUS NO CORRESPONDING WIND HAZARD IS POSTED.
ACROSS THE DESERT SOUTHWEST, TRIPLE-DIGIT DAYTIME TEMPERATURES ARE LIKELY TO
STRENGTHEN THE THERMAL LOW OVER THE SONORAN DESERT, WHICH COMBINED WITH THE
RIDGE AXIS POSITIONED NEAR THE FOUR CORNERS, IS EXPECTED TO ADVECT TROPICAL
MOISTURE NORTHWARD INTO THE REGION AND KICK OFF THE MONSOON SEASON. IN
ADDITION, THE NATIONAL HURRICANE CENTER (NHC) IS CURRENTLY MONITORING MULTIPLE
AREAS FOR TROPICAL CYCLONE (TC) DEVELOPMENT IN THE CENTRAL AND EASTERN PACIFIC,
WITH ONE AREA CLOSER TO MEXICO WITH 90% CHANCES FOR FORMATION (AS OF 1PM EDT)
DURING THE NEXT SEVEN DAYS. SHOULD FORMATION OCCUR NEXT WEEK, A POTENTIAL TRACK
NEARING THE GULF OF CALIFORNIA COULD INITIATE A GULF SURGE AND BRING ADDITIONAL
MOISTURE AND PRECIPITATION INTO THE SOUTHWEST. REGARDLESS OF THIS SCENARIO,
THERE CONTINUES TO BE GOOD SUPPORT IN THE GEFS AND ECMWF PETS INDICATING 20-40%
CHANCES FOR 3-DAY ACCUMULATED AMOUNTS EXCEEDING THE 85TH PERCENTILE, AND A
SLIGHT RISK OF HEAVY PRECIPITATION REMAINS POSTED FOR MUCH OF THE FOUR CORNERS
(JUL 19-23). THE FAVORED UPTICK IN MONSOONAL ACTIVITY IS LIKELY TO KEEP AN
EXCESSIVE HEAT RISK AT BAY DURING THE PERIOD, HOWEVER, MONSOONAL THUNDERSTORMS
CAN ALSO PRODUCE DRY LIGHTNING, RESULTING IN INCREASED WILDFIRE RISK. GIVEN THE
STRONG SIGNALS FOR ABOVE-NORMAL TEMPERATURES FURTHER NORTH, THERE IS ALSO AN
INCREASED RISK OF WILDFIRES ACROSS THE INTERIOR WEST AND HIGH PLAINS AS WELL.
FORECASTER: NICK NOVELLA
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