406
FXUS63 KDMX 022337
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
637 PM CDT THU APR 2 2026
...UPDATED FOR THE 00Z AVIATION DISCUSSION...
KEY MESSAGES
- SEVERE THUNDERSTORMS ARE EXPECTED TO CONTINUE AT TIMES IN
CENTRAL TO EASTERN IOWA THIS AFTERNOON. ALL SEVERE HAZARDS ARE
POSSIBLE.
- SEVERE STORMS FRIDAY AFTERNOON AND EVENING IN SOUTHERN HALF
OF IOWA WITH A ENHANCED RISK (LEVEL 3 OF 5) FOR SEVERE STORMS.
ALL SEVERE HAZARDS ARE POSSIBLE.
- COOLER AND QUITE THIS WEEKEND, COULD BECOME ACTIVE AGAIN LATER
NEXT WEEK.
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED AT 247 PM CDT THU APR 2 2026
WHILE LIGHT RAIN SHOWERS ARE PRESENT OVER PORTIONS OF EASTERN AND
NORTHEASTERN IOWA THIS AFTERNOON, THE MAIN FOCUS AREA OF CONCERN
TODAY IS AT THE CENTER OF THE LOW PRESSURE SYSTEM, WHICH AS OF 1PM
IS LOCATED RIGHT OVER NORTHWEST MISSOURI INTO SOUTHWEST IOWA. IN
THIS AREA, THE WARM FRONT IS ORIENTED WEST TO EAST FROM CRESTON
THROUGH OSKALOOSA, WHILE THE COLD FRONT IS ORIENTED JUST OVER
SOUTHWESTERN IOWA FROM ATLANTIC DOWN THROUGH CLARINDA. SHOWERS
AND THUNDERSTORMS HAVE RECENTLY DEVELOPED IN THIS AREA OF
INTEREST AS THE DRY SLOT MOVES IN AND AREAS OF CLEARING HAVE
BEEN NOTED. A FEW STORMS JUST NORTH OF THE IA/MO BORDER HAVE
GROWN UPSCALE IN STRENGTH, WHERE SEVERE THUNDERSTORM WARNINGS
WERE RECENTLY ISSUED FOR POTENTIAL DAMAGING WINDS AND HAIL. THE
EXPECTATION FOR THE REST OF THE AFTERNOON IS FOR ADDITIONAL
STORM DEVELOPMENT TO OCCUR OVER SOUTHERN INTO SOUTH CENTRAL IOWA
IN THE WARM SECTOR, RACING NORTHEASTWARD ACROSS THE AREA OVER
THE NEXT 4-5 HOURS. THE NEAR STORM ENVIRONMENT CONTINUES TO SHOW
INCREASING INSTABILITY VALUES AROUND 1000 J/KG AND SHEAR VALUES
AROUND 40-45+ KNOTS INTO THE STATE LATER THIS AFTERNOON, WHICH
WILL LEAD TO A MORE FAVORABLE ENVIRONMENT FOR STRONG TO SEVERE
STORMS. LAPSE RATES AROUND 7 C/KM AND GENERAL UNIDIRECTIONAL
SHEAR IS INDICATED, WHICH COULD LEAD TO HAIL PRODUCTION AND
DAMAGING WIND GUSTS, THOUGH MARGINAL IN NATURE. CURVING
HODOGRAPHS ARE INDICATED GIVEN SOME DIRECTIONAL SHEAR OVER THE
TRIPLE POINT, WITH HELICITY VALUES AROUND 200 M2/S2, WHICH LEADS
TO THE CONTINUED POTENTIAL FOR A FEW TORNADOES INTO THIS
EVENING. A TORNADO WATCH HAS BEEN ISSUED FOR OVER MUCH OF
SOUTHERN AND EASTERN IOWA UNTIL 8PM. STORMS ARE EXPECTED TO EXIT
THE REGION INTO THE EVENING, THOUGH REMAINING OVER FAR EASTERN
IOWA. COLD AIR WILL SURGE IN TONIGHT INTO FRIDAY BEHIND THE
DEPARTING SYSTEM, WITH OVERNIGHT LOWS EXPECTED TO FALL INTO THE
30S TO LOW 40S.
AFTER A BRIEF PERIOD OF QUIETER CONDITIONS FRIDAY MORNING, ANOTHER
MID-LEVEL TROUGH AND DEEPENING SURFACE LOW TO THE EAST OF THE
ROCKIES IS STILL EXPECTED TO PIVOT UP INTO SOUTHWESTERN IOWA BY THE
EARLY AFTERNOON, BRINGING THE NEXT POTENTIAL FOR SHOWERS AND STORMS
INTO IOWA. THE EXPECTATION REMAINS FOR THIS SYSTEM TO LIFT NORTHEAST
ACROSS THE STATE THROUGH THE AFTERNOON TO EVENING, WITH THE TRIPLE
POINT DIRECTLY OVERHEAD CENTRAL IOWA AROUND THE EARLY EVENING. CAM
GUIDANCE INDICATES THAT TWO ROUNDS OF ACTIVITY ARE EXPECTED TO
OCCUR: THE FIRST WAVE BEING NORTH OF THE WARM FRONT LIFTING ACROSS
WESTERN TO NORTHERN IOWA FROM ABOUT MID TO LATE MORNING, AND THE
SECOND JUST AHEAD OF THE WEST TO EAST TRACKING COLD FRONT, WHICH
LOOKS TO ENTER WESTERN IOWA AROUND 2-3 PM AND TRACK EASTWARD OVER
THE FORECAST AREA THROUGH ABOUT 9-10PM, BEFORE MOVING OUT OF THE
AREA.
REGARDING THE INITIAL WAVE THROUGH THE MORNING, PARTICULARLY OVER
WESTERN INTO NORTHWEST IOWA AS CAM GUIDANCE SHOWS THIS ROUND OF
CONVECTION DEVELOPING, THE PARAMETER SPACE FROM SOUNDINGS IN THESE
AREAS SHOWS INSTABILITY VALUES OF 500-1000 J/KG, ALONGSIDE SHEAR
VALUES OF 30-35 KNOTS, WHILE STEEP LAPSE RATES UP TO 8 C/KM AND
DIRECTIONAL SHEAR ARE ALSO INDICATED. FURTHER ANALYSIS SHOWS A WARM
LAYER IN THE LOW LEVELS THAT WOULD ALLOW FOR STORMS TO BE ELEVATED
IN NATURE, WITH THE MAIN HAZARD OF CONCERN WITH ANY STORMS LIKELY
BEING LARGE HAIL. AS MENTIONED ABOVE, ADDITIONAL STORMS ARE EXPECTED
TO DEVELOP AHEAD OF THE COLD FRONT LATER FRIDAY AFTERNOON AND
REMAINING THROUGH THE EVENING, WHERE THE ENVIRONMENT IN THE WARM
SECTOR FEATURES INSTABILITY VALUES AROUND 2000 J/KG, BULK SHEAR OF
40-50 KNOTS, AND TEMPERATURES RISE INTO THE 60S TO LOW 70S OVER THE
SOUTHERN HALF OF IOWA PAIRED WITH DEWPOINT VALUES INCREASING INTO
THE 50S TO LOW 60S. HELICITY VALUES IN THE LOW LEVEL UPWARDS OF 300-
400 M2/S2 AND STRONGER DIRECTIONAL SHEAR INDICATE A HIGHER TORNADO
THREAT MAINLY SOUTH OF I-80, WHERE THE ENHANCED RISK PER SPC
REMAINS. DAMAGING WINDS AND LARGE HAIL ARE ALSO POSSIBLE GIVEN THE
EXPECTED PARAMETER SPACE. PLEASE MAKE SURE TO HAVE MULTIPLE WAYS TO
RECEIVE WARNINGS THROUGH FRIDAY, AND HAVE A PLAN IN PLACE TO SHELTER
IN AREAS WHERE WARNING ARE ISSUED.
LONG TERM /SATURDAY THROUGH THURSDAY/
ISSUED AT 247 PM CDT THU APR 2 2026
DRYING WILL CONTINUE ACROSS THE STATE OVERNIGHT INTO SATURDAY, WITH
INCREASING NORTHWESTERLY FLOW AND COLD AIR ADVECTION BEHIND THE
DEPARTING SYSTEM TO THE NORTHEAST THAT WILL LEAD TO COOLER
CONDITIONS FOR THE DAY. HIGHS BY THE AFTERNOON ARE EXPECTED TO REACH
INTO THE 40S TO LOW 50S, ALONG WITH BREEZY CONDITIONS, ESPECIALLY
OVER NORTHWESTERN IOWA WITH GUSTS UP TO 35-40 MPH. WRAP AROUND
RAIN/SNOW CONTINUES IS POSSIBLE MAINLY OVER FAR NORTHERN IOWA,
THOUGH OVERALL IMPACTS, IF ANY, SHOULD BE MINIMAL AT THIS TIME AND
WILL CONTINUE TO BE MONITORED. SURFACE HIGH PRESSURE DESCENDS ACROSS
THE DAKOTAS INTO THE REGION SATURDAY NIGHT INTO SUNDAY, WITH
MIDLEVEL RIDGING EXPECTED TO BUILD THROUGH EARLY NEXT WEEK AND
COOLER AIR REMAINING OVERHEAD AS HIGHS GENERALLY REMAIN IN THE 50S
THROUGH AT LEAST TUESDAY.
AVIATION /00Z TAFS THROUGH 00Z SATURDAY/
ISSUED AT 637 PM CDT THU APR 2 2026
LOW CLOUDS WILL BLANKET THE AREA TONIGHT, PRODUCING IFR CEILINGS
INITIALLY BUT THEN IMPROVING TO MVFR BEFORE MIDNIGHT. IT IS
POSSIBLE DSM OR OTM MAY CLEAR OUT OVERNIGHT, AFTER 06Z, BUT MORE
LIKELY THE CEILINGS WILL PERSIST. FOG MAY ALSO DEVELOP OVERNIGHT
TOWARD SUNRISE FRIDAY, AND WOULD GENERALLY REMAIN AROUND 3-6SM
BUT IN ANY AREAS WHERE SKIES DO CLEAR, THEN THE FOG COULD BE
MORE DENSE WITH VISIBILITY FALLING TO 1SM OR LOWER. DURING THE
DAY FRIDAY MVFR CEILINGS WILL PREVAIL IN MOST AREAS, AND SHOWERS
AND THUNDERSTORMS WILL GRADUALLY SPREAD BACK IN, WHICH IS
INCLUDED WITH PROB30 GROUPS FOR NOW.
DMX WATCHES/WARNINGS/ADVISORIES
NONE.
SHORT TERM...BURY
LONG TERM...BURY
AVIATION...LEE
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