183
FXUS21 KWNC 141845
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT APRIL 14 2026
SYNOPSIS: LOW PRESSURE ALOFT AND AT THE SURFACE OVER THE HIGH PLAINS SUPPORTS
THE POTENTIAL FOR EPISODES OF HIGH WINDS THROUGHOUT MANY PARTS OF THE WEST,
GREAT PLAINS, AND MISSISSIPPI VALLEY, ALONG WITH AN ELEVATED RISK OF HEAVY
PRECIPITATION FOCUSED OVER THE LOWER AND MIDDLE MISSISSIPPI VALLEY. WHILE MANY
PORTIONS OF THE SOUTHEAST ARE INCREASINGLY FAVORED TO SEE NEAR TO ABOVE-NORMAL
PRECIPITATION DURING WEEK-2, ANTECEDENT DRYNESS COMBINED WITH UNSEASONABLY WARM
TEMPERATURES AND BELOW-NORMAL PRECIPITATION DURING WEEK-1 INCREASES THE RISK
FOR RAPID ONSET DROUGHT AND INTENSIFICATION OF DROUGHT OVER PARTS OF THE
SOUTHEASTERN U.S. OVER THE UPPER MIDWEST, FLOODING IS POSSIBLE ASSOCIATED WITH
PERSISTENT ABOVE-NORMAL PRECIPITATION ACCELERATING SPRING SNOWMELT OVER THE
NEXT TWO WEEKS.
HAZARDS
MODERATE RISK OF HEAVY PRECIPITATION FOR PORTIONS OF THE MIDDLE AND LOWER
MISSISSIPPI, TENNESSEE AND OHIO VALLEYS, THU-FRI, APR 23-24.
SLIGHT RISK OF HEAVY PRECIPITATION FOR PORTIONS OF THE SOUTHERN PLAINS,
MISSISSIPPI, TENNESSEE, AND OHIO VALLEYS, WED-SAT, APR 22-25.
SLIGHT RISK OF HIGH WINDS FOR PARTS OF THE GREAT BASIN, SOUTHWEST, ROCKIES,
GREAT PLAINS, AND MISSISSIPPI VALLEY, WED-SAT, APR 22-25.
POSSIBLE FLOODING FOR PARTS OF THE GREAT LAKES REGION AND UPPER AND MIDDLE
MISSISSIPPI VALLEY.
RAPID ONSET DROUGHT RISK ACROSS PARTS OF MISSISSIPPI, ALABAMA, GEORGIA, AND
SOUTH CAROLINA.
DETAILED SUMMARY
FOR FRIDAY APRIL 17 - TUESDAY APRIL 21:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR WEDNESDAY APRIL 22 - TUESDAY APRIL 28: MULTIPLE DYNAMICAL MODELS CONTINUE
TO ADVERTISE A PROGRESSIVE MID-LEVEL HEIGHT PATTERN DURING WEEK-2. DOWNSTREAM
OF A 500-HPA RIDGE OVER THE NORTHEASTERN PACIFIC, BOTH THE GEFS AND ECMWF
ENSEMBLES CONTINUE TO FEATURE CYCLONIC FLOW PREVAILING THROUGHOUT THE INTERIOR
WEST, WITH A NARROW RIDGE AXIS FOCUSED ACROSS THE GREAT PLAINS AND MISSISSIPPI
VALLEY EARLY IN WEEK-2. OVER TIME, ENSEMBLES HAVE TRENDED TOWARDS DEVELOPING A
MORE AMPLIFIED MEAN TROUGHING SOLUTION FOCUSED OVER THE SOUTHWESTERN CONUS,
WHILE CONTINUING TO BREAK DOWN THE RIDGING DOWNSTREAM EAST OF THE ROCKIES LATER
NEXT WEEK. FURTHER NORTH, HOWEVER, THE MOST NOTABLE TREND IN THE MODELS
CONCERNS THE DEVELOPMENT OF AN AMPLIFIED RIDGE CENTERED OVER THE DAVIS STRAIT
CONSISTENT WITH A NEGATIVE NORTH ATLANTIC OSCILLATION (-NAO) PATTERN. SUCH A
PATTERN SHIFT MAY BE DRIVEN BY A STRENGTHENING MADDEN-JULIAN OSCILLATION (MJO)
IN THE WESTERN PACIFIC. WHILE MODELS FAVOR MUCH OF THE LONGWAVE TROUGHING TO
DEVELOP OVER THE WESTERN ATLANTIC LATE IN THE PERIOD, ANY PERSISTENCE OF A
BLOCKING HIGH OVER NORTHEASTERN CANADA COULD ALLOW A TRANSITION FOR COOLER
TEMPERATURES FOR MUCH OF THE CENTRAL AND EASTERN CONUS LATER IN APRIL.
TIED TO THE MID-LEVEL TROUGHING FAVORED OVER THE INTERIOR WEST, SURFACE LOW
DEVELOPMENT IS FAVORED IN THE LEE OF THE ROCKIES WHERE BOTH THE GEFS AND ECMWF
HAVE COME INTO BETTER AGREEMENT FEATURING A MEAN LOW CENTER OVER WESTERN
NEBRASKA AND WESTERN KANSAS BY THE OUTSET OF WEEK-2. WITH MEAN SURFACE HIGH
PRESSURE FAVORED TO BE ESTABLISHED OVER THE SOUTHEAST AND MID-ATLANTIC
SUPPORTING ENHANCED LOWER-LEVEL MOISTURE INTO PARTS OF THE GREAT PLAINS,
MISSISSIPPI AND TENNESSEE VALLEYS, THE SYNOPTIC PATTERN LOOKS MORE CONDUCIVE
FOR POTENTIALLY HEAVY PRECIPITATION RELATIVE TO YESTERDAY. BASED ON AN OVERALL
UPTICK IN SIGNALS IN THE RAW AND CALIBRATED PRECIPITATION TOOLS, A MODERATE
RISK OF HEAVY PRECIPITATION IS POSTED FOR APR 23-24 OVER THE LOWER AND MIDDLE
MISSISSIPPI VALLEY AND ADJACENT MISSISSIPPI-OHIO RIVER CONFLUENCE WHERE THE RAW
GEFS AND ECMWF SHOW AT LEAST 40% CHANCES OF 3-DAY PRECIPITATION AMOUNTS
EXCEEDING AN INCH. DESPITE THIS HIGHER RISK DESIGNATION IN THE UPDATED OUTLOOK,
THERE CONTINUES TO BE ADDED UNCERTAINTY IN REGARDS TO WHETHER THIS
PRECIPITATION RISK SHIFTS EASTWARD WITH TIME. THE ECMWF EJECTS MUCH OF THE
SHORTWAVE TROUGHING WITH WETTER CONDITIONS UNFOLDING OVER SOUTHEAST, WHEREAS
THE GEFS MAINTAINS A MORE WESTERLY SOLUTION OF THE MEAN TROUGHING ALOFT
RESULTING IN A COMPARABLY DRIER PICTURE FOR THIS PART OF THE COUNTRY. TO
RECONCILE THESE DIFFERENCES ALOFT AND IN THE PRECIPITATION TOOLS, A SLIGHT RISK
REMAINS POSTED AND IS EXPANDED SLIGHTLY SOUTHEASTWARD TO INCLUDE PORTIONS OF
THE SOUTHERN PLAINS, MISSISSIPPI, TENNESSEE, AND OHIO VALLEYS AND ALSO EXTENDED
THROUGH APR 25 WHERE UNCALIBRATED TOOLS SHOW LESSER (20-40%) CHANCES OF 3-DAY
AMOUNTS EXCEEDING AN INCH THROUGH THE MIDDLE OF THE PERIOD. OF NOTE,
ACCUMULATING SNOWFALL IS POSSIBLE ON THE BACKSIDE OF THE MEAN SURFACE LOW OVER
THE FRONT RANGE. A CORRESPONDING HEAVY SNOW RISK WAS CONSIDERED IN THE UPDATED
OUTLOOK, HOWEVER THERE IS A LACK OF ENSEMBLE SUPPORT FOR AMOUNTS EXCEEDING
HAZARD CRITERIA FOR THE HIGHER ELEVATIONS.
DUE TO ANTECEDENT DRYNESS COMBINED WITH UNSEASONABLY WARM TEMPERATURES AND
BELOW-NORMAL PRECIPITATION FAVORED OVER THE SOUTHEASTERN CONUS DURING WEEK-1, A
RAPID ONSET DROUGHT (ROD) RISK REMAINS ISSUED FOR PARTS OF MISSISSIPPI,
ALABAMA, GEORGIA, AND SOUTH CAROLINA. HOWEVER, THIS RISK WILL BE CLOSELY
MONITORED FOR REMOVAL IN UPCOMING OUTLOOKS SHOULD MODELS COME INTO A BETTER
CONSENSUS WITH THE HEAVY PRECIPITATION RISK SHIFTING INTO THESE HIGHLIGHTED
AREAS.
WITH ABOVE-NORMAL SNOWPACK AND ABOVE-NORMAL PRECIPITATION BEING REGISTERED FOR
MUCH OF THE GREAT LAKES, SEASONAL SPRING MELT HAS LED TO SATURATED SOILS AS
WELL AS WIDESPREAD RIVER FLOODING, THUS ANY ADDITIONAL WATER IN THE RIVER
SYSTEMS WILL NOT BE EASILY ACCOMMODATED. MUCH OF THE GREAT LAKES REMAINS
FAVORED FOR ABOVE-NORMAL PRECIPITATION DURING THE NEXT TWO WEEKS, WHICH COULD
RESULT IN ACCELERATED SNOW MELT EXACERBATING THE FLOODING POTENTIAL. A FLOODING
POSSIBLE HAZARD IS POSTED FOR PARTS OF THE GREAT LAKES REGION AND UPPER AND
MIDDLE MISSISSIPPI VALLEY, WHERE THE CONFLUENCE OF THESE PARAMETERS IS
GREATEST. HOWEVER, THE THREAT OF FLOODING IS NOT LIMITED TO THESE AREAS ALONE,
AS LINGERING SNOW REMAINS ON THE GROUND OVER PORTIONS OF THE HIGH PLAINS AS
WELL. NO HAZARD IS ISSUED FOR THE RED RIVER OF THE NORTH OR OTHER WATERCOURSES
IN THE REGION, ALTHOUGH RIVER RISES ARE LIKELY AS SNOW MELTS AND LOCALIZED
FLOODING MAY OCCUR.
THE FAVORED PERSISTENCE OF CYCLONIC FLOW ALOFT ACROSS MUCH OF THE WESTERN CONUS
AND SURFACE LOW DEVELOPMENT IN THE GREAT PLAINS SUPPORTS AN INCREASED RISK OF
PERIODS OF ELEVATED WINDS DURING WEEK-2. A BROAD SLIGHT AREA OF HIGH WINDS
REMAINS ISSUED FOR THE HIGHER ELEVATIONS OF THE INTERIOR WEST EASTWARD TO THE
MISSISSIPPI VALLEY (APR 22-25) WHERE UNCALIBRATED TOOLS SHOW INCREASED CHANCES
FOR WIND GUSTS EXCEEDING 34KTS (~40MPH) THROUGH THE MIDDLE OF THE WEEK-2. GIVEN
THE EXTREMELY DRY WINTER EXPERIENCED OVER THE WEST, ANY SUCH WINDS REALIZED MAY
PRESENT A POTENTIAL WILDFIRE HAZARD.
NO HAZARDS ARE ISSUED OVER ALASKA, BUT FLOODING CAN OCCUR THIS TIME OF YEAR
WITH LITTLE OR NO NOTICE DURING RIVER ICE BREAKUP SEASON. THE COLDER
TEMPERATURES IN THE WEEK-2 OUTLOOK INCREASE THE CHANCES OF DELAYED RIVER
BREAKUP IN ALASKA AND INCREASE THE CHANCES OF ICE JAM FLOODING. CHECK THE
ALASKA PACIFIC RIVER FORECAST CENTER (HTTPS://WWW.WEATHER.GOV/APRFC/BREAKUPMAP)
FOR THE LATEST CONDITIONS OR ADVISORIES.
FORECASTER: NICK NOVELLA
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