640
FXUS63 KDMX 272010
AFDDMX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
210 PM CST THU FEB 27 2025
KEY MESSAGES
- STRONG WINDS/FIRE CONCERNS FRIDAY
- BRIEF COOLDOWN SATURDAY; THEN WARMING AGAIN WITH CHANCE
RAIN/SNOW (25-35%) MONDAY.
- STRONG MIDWEEK SYSTEM BRINGS POTENTIAL MIX AND GREATER
AMOUNTS OF PRECIPITATION TO THE REGION.
DISCUSSION
ISSUED AT 210 PM CST THU FEB 27 2025
SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/
CONFIDENCE: MEDIUM TO HIGH
MODIFIED ZONAL PATTERN CONTINUES WITH SOME NORTHWESTERLY COMPONENT
STILL EVIDENT OVER THE NORTHERN PLAINS TO GREAT LAKES. MEAN TROUGH
STILL JUST TO OUR EAST AND WILL LIKELY AID IN AMPLIFICATION OF ANY
WAVE ENTERING THE BACKSIDE OF THE TROUGH NEXT WEEK. H850 ANALYSIS
CONTINUES TO SHOW WEAK COLD AIR ADVECTION TODAY WITH WARMER AIR
ALREADY OVER THE ROCKIES/NORTHERN PLAINS EXPECTED TO ARRIVE
OVERNIGHT INTO FRIDAY MORNING. OUR MAIN CONCERNS WILL BE WINDS
TOMORROW AS WELL AS FIRE WEATHER CONCERNS. WINDS ALOFT WILL
INCREASE OVERNIGHT AND PEAK AT AROUND 45 TO 50 MPH DURING THE
AFTERNOON HOURS AS NORTHWEST FLOW AND SUBSIDENCE INCREASES DURING
THIS TIME. WE MAY SEE A FEW LOCATIONS PEAK AROUND 55 MPH, BUT WILL
NOT EXPECT THIS REGIONWIDE. THIS WILL RESULT IN DEEP MIXING WITH
LOWERING RH OVER MUCH OF THE SOUTH TWO THIRDS OF THE FORECAST AREA;
GENERALLY SOUTH OF HIGHWAY 20. HOWEVER, THE STRONGEST WINDS/GUSTS
ARE ANTICIPATED TO BE OVER THE FAR NORTHERN COUNTIES. A THERMAL
TROUGH WILL BE ENTERING IOWA OVERNIGHT AND BEGINNING TO EXIT THE
REGION AFTER 12Z. DESPITE THE WARMEST AIR ALOFT OCCURRING OVERNIGHT,
WE WILL STILL TAP INTO -3C NORTH TO 5C SOUTH AIR THROUGH 18Z, WITH
COLD AIR ADVECTION BECOMING MORE INTRUSIVE IN THE NORTH BETWEEN 21
AND 00Z. A WIND ADVISORY WILL BE NEEDED FOR NEARLY ALL BUT THE
SOUTHERN/FEW SOUTHWEST COUNTIES OF THE REGION. A RED FLAG WARNING
WILL ALSO BE ISSUED FOR MOST OF THE AREA TOMORROW WITH THE NORTH
SEEING THE STRONGEST WINDS AND THE SOUTH SEEING THE LOWEST RELATIVE
HUMIDITY DURING THIS TIMEFRAME. AFTER SOME DELIBERATION AND
COORDINATION, WE WILL LEAVE THE FAR NORTHERN COUNTIES OUT OF THE RFW
FOR NOW, GIVEN SLIGHTLY HIGHER MINIMUM RH IN THE AFTERNOON AND MORE
RAPID COOLING AS COLD AIR ADVECTION ADVANCES SOUTH DURING THE
AFTERNOON HOURS. WINDS WILL BE STRONGEST OVER THE NORTH, HOWEVER AND
A WIND ADVISORY IS IN PLACE FOR MOST OF THE REGION EXCEPT FOR THE
FAR SOUTH/ SOUTHWEST. FURTHER EVALUATION OVERNIGHT TONIGHT MAY ADD
SOME COUNTIES FOR ONE OR BOTH HEADLINES. TONIGHT WILL BE MILDER WITH
THE THERMAL TROUGH PASSING THROUGH AND TOMORROW WILL SEE HIGHS
PEAKING IN THE EARLY AFTERNOON MOST AREAS WITH LOWER 50S NORTH
TO THE LOWER 60S IN THE SOUTH.
LONG TERM /SATURDAY THROUGH THURSDAY/
CONFIDENCE: MEDIUM LOWERING TO LOW TO MEDIUM TUES/WED
AFTER A BRIEF COOLDOWN SATURDAY AND SUNDAY WITH MORE SEASONAL
TEMPERATURES FOR LATE FEBRUARY/EARLY MARCH, WE WILL SEE MILDER AIR
RETURN MONDAY. HIGHS SATURDAY/SUNDAY WILL REMAIN IN THE 30S/40S.
MODELS ARE NOW IN AGREEMENT WITH A WAVE DEVELOPING IN THE CENTRAL
PLAINS SUNDAY, AND LIFTING NORTHEAST WITH ISENTROPIC LIFT/SATURATION
PRECIPITATION SUNDAY NIGHT INTO EARLY MONDAY MORNING. CHANCES FOR
ANY PRECIPITATION ARE IN THE 25 TO 35% RANGE AND SHOULD END BY
MIDDAY. GUIDANCE WITHIN THE ENSEMBLE SUITES OF THE GFS/EC DIFFER ON
THE EVOLUTION OF NEXT WEEKS SYSTEM(S). THE GFS SUITE HAS TWO
DISTINCT WAVES AND A MORE SIGNIFICANT FIRST WAVE COMPARED TO THE EC
WHICH HAS ONLY A WEAK SUN/MON SYSTEM TRACKING THROUGH AND THEN THE
MAIN WAVE FOR TUES/WED. BOTH MODELS SHOW CONSOLIDATION AND
AMPLIFICATION AS THE MAIN SYSTEM TRACKS NORTHEAST TUESDAY AND
TUESDAY NIGHT WITH THE FIRST REAL OPPORTUNITY FOR SIGNIFICANT STORM
AND MOISTURE IN OUR AREA FOR QUITE SOME TIME. BOTH THE GEFS/EC MEAN
PRECIP ACCUMULATION THROUGH THE PERIOD IS FAVORING A HALF INCH
CENTRAL TO INCH SOUTHEAST WITH THIS SYSTEM. THERMAL TRENDS DIFFER
FOR NOW, WITH THE EC SUITE COLDER WITH A MORE LIKELIHOOD OF SNOW
WITH LIQUID PRECIPITATION. THOUGH BOTH DETERMINISTIC ARE SUGGESTING
SNOW OVER THE SOUTH/SOUTHEAST HALF OF OUR AREA TUESDAY NIGHT, THE EC
CURRENTLY HAS SLIGHTLY GREATER TOTALS. WITH A FAIR AMOUNT OF
UNCERTAINTY EXPECTED THE NEXT FEW DAYS, WILL CONTINUE TO EVALUATE
INTO THE WEEKEND. AS THE SYSTEM EXITS, WE WILL BE SEEING A RETURN OF
MILDER AIR TO ROUND OUT THE EXTENDED. WITH THE AMOUNT OF UNCERTAINTY
INTO NEXT WEEK, TEMPERATURES CURRENTLY FORECAST TUESDAY/WEDNESDAY
APPEAR TOO WARM, WITH THE EXCEPTION OF THE FAR SOUTHEAST. THE SOUTH
AND SOUTHEAST MAY BE IN LINE FOR SOME GENERAL THUNDER, WHILE SOME
INSTABILITY WITHIN THE SNOW IS ALSO SHOWING UP IN SOME OF THE
GUIDANCE. HIGHS IN THE 50S WILL BE COMMON MONDAY. BY TUESDAY, WE
WILL PROBABLY SEE A MUCH HIGHER SPREAD FROM NORTHWEST TO SOUTHEAST
WITH 50S/60 SOUTHEAST TO THE 30S FAR NORTHWEST. WEDNESDAY INTO
THURSDAY HAVE LOW PREDICTABILITY DUE TO POTENTIAL SNOW COVER.
AVIATION /18Z TAFS THROUGH 18Z FRIDAY/
ISSUED AT 1145 AM CST THU FEB 27 2025
MAIN CONCERN WILL BE WINDS AFT 12Z AND WIND SHEAR AFT 06Z AND
LASTING THROUGH AROUND 12-15Z. RATHER DEEP MIXING IS ANTICIPATED
FROM 15Z FRIDAY THROUGH 00Z SATURDAY (NEXT FORECAST PERIOD),
WITH SOME GUSTS OCCASIONALLY REACHING 40 TO 45KTS 18Z THROUGH
00Z SATURDAY - JUST A HEADS UP. TROUGH PASSAGE AROUND 12Z
SIGNALS A WIND SHIFT TO WEST FOLLOWED BY A NORTHWEST WIND AFT
15Z THROUGH REMAINDER OF PERIOD. /REV
DMX WATCHES/WARNINGS/ADVISORIES
WIND ADVISORY FROM 10 AM TO 6 PM CST FRIDAY FOR IAZ004>007-
015>017-023>028-033>039-044>050-057>062-073>075.
RED FLAG WARNING FROM NOON TO 6 PM CST FRIDAY FOR IAZ023>028-
033>039-044>050-057>062-070>075-081>086-092>097.
DISCUSSION...REV
AVIATION...REV
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