381
FXUS63 KOAX 170509
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1209 AM CDT FRI JUL 17 2026
KEY MESSAGES
- PATCHY FOG IS POSSIBLE OVERNIGHT, FOLLOWED BY HIGHS IN THE
90S TO NEAR 100 FRIDAY. ISOLATED SHOWERS ARE POSSIBLE FRIDAY
AFTERNOON.
- HEAT BUILDS THIS WEEKEND, WITH HEAT INDEX VALUES REACHING 100
TO 108 DEGREES SUNDAY AND MONDAY.
- COOLER WEATHER RETURNS BY MIDWEEK, ALONG WITH INCREASING
CHANCES FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT INTO
THURSDAY.
DISCUSSION
ISSUED AT 1029 PM CDT THU JUL 16 2026
TONIGHT AND FRIDAY...
MID- TO UPPER-LEVEL RIDGING REMAINS IN PLACE ACROSS THE CENTRAL
CONUS, SUPPORTING CONTINUED WARM AND GENERALLY QUIET
CONDITIONS. A FEW ISOLATED, DIURNALLY DRIVEN SHOWERS DEVELOPED
THIS AFTERNOON. FOG DEVELOPMENT IS EXPECTED AGAIN OVERNIGHT INTO
FRIDAY MORNING. FORECAST SOUNDINGS DEPICT A SHALLOW SATURATED
LAYER NEAR THE SURFACE WITH GUSTY WINDS ABOVE IT. AS A RESULT,
FOG SHOULD REMAIN PATCHY AND LARGELY CONFINED TO LOW-LYING AND
WIND PROTECTED AREA, ALONG WITH SCATTERED AREAS THAT RECEIVED
HEALTHY RAIN SHOWERS THIS AFTERNOON.
TEMPERATURES WILL TREND SLIGHTLY WARMER FRIDAY, WITH HIGHS
RANGING FROM THE LOWER 90S TO NEAR 100 DEGREES ALONG THE
NEBRASKA-SOUTH DAKOTA BORDER. CONTINUED LOW-LEVEL THETA-E
ADVECTION AND EVAPOTRANSPIRATION WILL MAINTAIN MUGGY DEWPOINTS
IN THE UPPER 60S TO LOW 70S, RESULTING IN PEAK HEAT INDEX VALUES
IN THE UPPER 90S TO LOWER 100S. CAN'T RULE OUT A FEW ADDITIONAL
WIDELY SCATTERED DIURNALLY DRIVEN SHOWERS DURING THE AFTERNOON
(20% CHANCE), GENERALLY ALONG AND SOUTH OF I-80 WHERE THE BETTER
INSTABILITY RESIDES. WHILE INSTABILITY IS PLENTIFUL, SHEAR WILL
REMAIN VERY WEAK, LIMITING ANY SEVERE WEATHER POTENTIAL AND
LIKELY KEEP SHOWERS RELATIVELY STATIONARY. A LOCALIZED DOWNPOUR
AND RUMBLE OF THUNDER REMAIN THE PRIMARY HAZARD.
SATURDAY THROUGH MONDAY...
TEMPERATURES WILL CONTINUE TO CLIMB THROUGH THE PERIOD AS THE MID-
LEVEL RIDGE AXIS SHIFTS TOWARD THE WESTERN HIGH PLAINS AND WARMER
850 MB TEMPERATURES SPREAD INTO THE REGION. HIGHS SATURDAY WILL
REACH THE MID TO UPPER 90S, WITH HEAT INDEX VALUES GENERALLY IN THE
UPPER 90S TO LOW 100S. TEMPERATURES WILL INCREASE FURTHER SUNDAY,
WITH HIGHS RANGING FROM THE MID 90S TO AROUND 105 DEGREES. THE
WARMEST READINGS ARE EXPECTED ACROSS NORTHEAST NEBRASKA, WHILE HEAT
INDEX VALUES RANGE FROM THE UPPER 90S TO AROUND 106 DEGREES.
SUNDAY, A SHORTWAVE TROUGH PUSHING INTO THE NORTHERN PLAINS IS
EXPECTED TO INITIATE OVERNIGHT CONVECTION, POTENTIALLY
ORGANIZING INTO AN MCS. ENSEMBLE GUIDANCE HAS CONSISTENTLY KEPT
THE STRONGEST SIGNAL NORTH OF THE FORECAST AREA, PRIMARILY
ACROSS SOUTH DAKOTA. HOWEVER, SOME OF THIS ACTIVITY COULD GRAZE
NORTHEAST NEBRASKA, WHERE POPS OF 15% REMAIN IN PLACE SUNDAY
NIGHT. THE DISTURBANCE WILL ALSO HELP PUSH A COLD FRONT INTO THE
AREA SUNDAY. DESPITE THE NAME, THE FRONT IS NOT EXPECTED TO
PROVIDE MUCH RELIEF, THOUGH IT MAY LOWER DEWPOINTS BY A DEGREE
OR TWO ACROSS NORTHEAST NEBRASKA.
MONDAY CONTINUES TO HAVE THE WARMEST TEMPERATURES IN THE
FORECAST, WITH WIDESPREAD HIGHS FROM 99 TO 105 DEGREES AND PEAK
HEAT INDEX VALUES FROM 100 TO AROUND 108 DEGREES. THE HIGHEST
HEAT INDEX VALUES ARE EXPECTED ACROSS SOUTHWEST IOWA, WHERE
DEWPOINTS WILL BE THE HIGHEST. CONFIDENCE IN MONDAY'S
TEMPERATURES IS SLIGHTLY LOWER DUE TO THE POTENTIAL FOR
OVERNIGHT CONVECTION TO THE NORTH. A SOUTHWARD SHIFT IN
CONVECTION OR LINGERING CLOUD COVER COULD LIMIT DAYTIME HEATING.
HEAT HEADLINES WILL LIKELY BE NEEDED FOR PORTION OF THE PERIOD. HEAT
INDEX VALUES ARE GENERALLY NEAR HEAT ADVISORY CRITERIA, WITH
OVERNIGHT LOWS REMAINING IN THE LOW TO MID 70S, PROVIDING LITTLE
RELIEF. THE DURATION OF THE HEAT AND WARM OVERNIGHT TEMPERATURES
WILL SUPPORT WIDESPREAD HIGH HEATRISK, PARTICULARLY SUNDAY AND
MONDAY.
TUESDAY AND BEYOND...
COOLER TEMPERATURES AND INCREASING PRECIPITATION CHANCES ARE
EXPECTED DURING THE PERIOD AS A SHORTWAVE TROUGH PUSHING INTO THE
NORTHERN PLAINS DAMPENS THE RIDGE AND PUSHES ANOTHER COLD FRONT
THROUGH THE AREA MONDAY NIGHT. HIGHS TUESDAY ARE STILL EXPECTED TO
REACH THE LOW TO MID 90S, WITH HIGH TEMPERATURES FALLING INTO THE
80S WEDNESDAY AND THURSDAY AS COOLER AIR AND CLOUD COVER RETURNS TO
THE REGION. THE BEST PRECIPITATION CHANCES CURRENTLY APPEAR TO BE
WEDNESDAY NIGHT INTO THURSDAY, WHEN ANOTHER SHORTWAVE PASSAGE
SUPPORTS POPS OF 30-50%.
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 1206 AM CDT FRI JUL 17 2026
VFR CONDITIONS A CURRENTLY IN PLACE THIS EVENING WITH ONLY A FEW
CLOUDS NEAR KOMA INTERRUPTING THE NIGHT SKY AT FL100, WITH THE
MAIN CONCERN BEING THE POSSIBILITY OF PATCHY FOG AFTER 09Z.
CONFIDENCE IN ITS FORMATION IS A BIT LOWER THAN IT HAS BEEN OVER
THE PAST FEW DAYS, OWING TO A BIT OF WIND AT FL020 THAT COULD
KEEP THE SURFACE STIRRED UP JUST ENOUGH TO PREVENT ITS
FORMATION. OTHERWISE, WINDS WILL STAY OUT OF THE SOUTHEAST,
PICKING UP LATE TOMORROW MORNING TO NEAR 10 KTS WHILE THE
AFTERNOON TRIES TO SEE A FEW POP-UP SHOWERS AND STORMS. AS OF
NOW, THE CHANCES FOR ANY TAF LOCATION TO BE AFFECTED BY ONE IS
ABOUT 20%, AND WILL BE KEPT OUT OF THE TAF FOR NOW.
OAX WATCHES/WARNINGS/ADVISORIES
NE...NONE.
IA...NONE.
DISCUSSION...WOOD
AVIATION...PETERSEN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page