856
FXUS63 KEAX 291727
AFDEAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1227 PM CDT THU JUL 29 2021
DISCUSSION
ISSUED AT 404 AM CDT THU JUL 29 2021
KEY POINTS:
-ANOTHER HOT DAY TODAY WITH WIDESPREAD HEAT INDEX VALUES NEAR 105
F.
-COLD FRONT IS EXPECTED TO BUILD INTO THE REGION THIS AFTERNOON.
THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR THE FRONT AFTER 4 PM CDT.
A FEW STORMS MAY PRODUCE GUSTY WINDS TO 65 MPH, AND PERHAPS HAIL UP
TO 1" IN DIAMETER.
-COLD FRONT IS EXPECTED TO STALL ACROSS THE AREA, WITH AREAS SOUTH
AND WEST OF A LINE FROM THE KC METRO TO SEDALIA WARMING TO HEAT
INDICES NEAR 105 F ON FRIDAY. HAVE EXTENDED HEAT ADVISORY FOR THESE
LOCATIONS THROUGH FRIDAY EVENING.
DETAILED DISCUSSION...
MUGGY ENVIRONMENT REMAINS IN PLACE WITH LARGE UPPER RIDGE DOMINATING
WEST OF THE MISSISSIPPI RIVER. AT THE SURFACE, ELONGATED HIGH
PRESSURE ALONG THE GULF COAST LEADING TO MORE CONSISTENT SOUTHERLY
FLOW ACROSS THE REGION TODAY. WITH ABUNDANT MOISTURE ACROSS THE
CENTRAL AND SOUTHERN PLAINS, WILL SEE MOISTURE INCREASE ACROSS THE
REGION TODAY AS A COLD FRONT APPROACHES FROM THE NORTH. AS OF 08Z,
COLD FRONT WAS LOCATED NEAR HIGHWAY 20 IN NORTHERN IOWA. FRONT IS
EXPECTED TO REACH THE IOWA/MISSOURI BORDER EARLY THIS AFTERNOON,
WITH NEARLY 4000-45000 J/KG OF SB CAPE AHEAD OF THE FRONT. AS THE
FRONT MOVES THROUGH, CAPPING INVERSION LOOKS TO WEAKEN TO THE POINT
THAT CONVECTION IS EXPECTED TO DEVELOP ACROSS NORTHERN/NORTHEAST
MISSOURI. HAVE RAISED POPS THROUGH THE AFTERNOON AND EVENING HOURS
IN THE VICINITY OF THE FRONT. 0-6 KM BULK SHEAR IS ~20-25 KNOTS
ACROSS NORTHEAST MISSOURI, ENOUGH TO WHERE A FEW UPDRAFTS MAY
APPROACH SEVERE LIMITS. WITH WARM ENVIRONMENT, WILL BE HARD TO GET
HAIL TO THE SURFACE. WITH MOISTURE POOLING NEAR THE FRONT,
PRECIPITABLE WATER VALUES ARE EXPECTED TO BE NEAR 2", AND DEEP
WARM CLOUD DEPTHS SHOULD PROMOTE TROPICAL RAIN PROCESSES. WHILE
STORMS WILL BE MOVING AROUND 25-30 KNOTS TO THE SOUTHEAST, STILL
COULD BE EFFICIENT ENOUGH TO PRODUCE LOCALLY HEAVY RAINFALL. WPC
HAS OUTLINE NE MISSOURI IN MARGINAL THREAT FOR EXCESSIVE RAINFALL.
EXPECT CONVECTION TO WANE THROUGH THE EVENING AS FRONT WORKS TOWARDS
THE I-70 CORRIDOR. MUGGY AIRMASS WILL REMAIN SOUTH OF THE FRONT,
AND EXPECT A FAIRLY STARK CONTRAST IN CONDITIONS FROM AHEAD AND
BEHIND THE FRONT ON FRIDAY. NORTH OF THE FRONT, EXPECT TEMPERATURES
TO REMAIN IN THE 80S, WHILE FARTHER SOUTH, EXPECT HIGHS TO WARM INTO
THE 90S ONCE AGAIN WITH DEW POINTS WELL INTO THE 70S. GIVEN ONE
FINAL DAY OF HEAT AND HUMIDITY IS EXPECTED, COORDINATED EXTENDING
THE HEAT ADVISORY THROUGH FRIDAY EVENING SOUTH AND WEST OF A LINE
FROM ST JOESPH TO SEDALIA. IN THIS AREA HEAT INDEX VALUES APPEAR TO
WARM TO NEAR 105 F ONCE AGAIN FRIDAY AFTERNOON. IF
TEMPERATURES/HEAT INDEX VALUES WARM FURTHER, DAY SHIFT MAY NEED TO
CONSIDER A EXCESSIVE HEAT WARNING.
A SERIES OF SHORT WAVES ARE EXPECTED TO MOVE INTO IOWA FRIDAY
EVENING, LEADING TO ADDITIONAL CONVECTION DEVELOPING ACROSS THE UPPER
MIDWEST. THIS CONVECTION IS EXPECTED TO BUILD INTO MISSOURI FRIDAY
NIGHT AS MOISTURE INCREASES IN THE 800-650 MB LAYER. WHILE
INSTABILITY IS LIMITED NORTH OF THE STALLED BOUNDARY, WIND SHEAR IS
MUCH BETTER WITH 40-50 KNOTS OF 0-6 KM BULK SHEAR. WHERE INSTABILITY
AND BETTER SHEAR OVERLAP, COULD SEE A FEW STRONG- SEVERE STORMS.
LINGERING MUGGY AIRMASS WILL BE THE FOCUS FOR RENEWED CONVECTIVE
CHANCES ON SATURDAY MORNING, BUT SHOULD GRADUALLY WORK SOUTH LEADING
TO COOLER AND DRIER CONDITIONS FORECAST AREA WIND THROUGH THE
REMAINDER OF THE WEEKEND INTO NEXT WEEK. HIGH TEMPERATURES SUNDAY -
WEDNESDAY APPEAR TO BE IN THE MID 80S, WITH LOWS IN THE LOWER 60S.
GREAT WEATHER TO AIR THE HOUSE OUT!
AVIATION
(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1226 PM CDT THU JUL 29 2021
VFR CONDITIONS THROUGH THE PERIOD. SCATTERED THUNDERSTORMS ARE
EXPECTED TO REMAIN TO THE NORTH OF TERMINAL SPACE DURING THE
FORECAST PERIOD.
EAX WATCHES/WARNINGS/ADVISORIES
KS...HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR KSZ025-057-060-102>105.
MO...HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MOZ001>008-011>017-
021>025-030>033-038>040-046.
HEAT ADVISORY UNTIL 9 PM CDT FRIDAY FOR MOZ020-028-029-037-
043>045-053-054.
DISCUSSION...BT
AVIATION...BLAIR
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page