859  
FXUS63 KFSD 221736  
AFDFSD  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SIOUX FALLS SD  
1236 PM CDT MON JUL 22 2019  
   
SHORT TERM
 
(TODAY AND TONIGHT)  
ISSUED AT 252 AM CDT MON JUL 22 2019  
 
BEAUTIFUL START TO THE WORK WEEK WITH DRIER AND COOLER CONDITIONS  
DOMINATING THE REGION. CLOUDS WILL CONTINUE TO DECREASE EARLY THIS  
MORNING, AS A SURFACE HIGH PRESSURE CURRENTLY OVER NORTH DAKOTA  
MOVES SOUTH AND BUILDS IN OVER OUR AREA. NORTHERLY FLOW ALOFT WILL  
MAINTAIN A MILD AIRMASS, WITH TEMPERATURES TODAY REACHING THE UPPER  
70S TO LOW 80S. THERE WILL BE A WEAK VORT MAX MOVING SOUTH FROM EAST  
CENTRAL SD INTO SOUTHWEST MINNESOTA DURING THE AFTERNOON HOURS. WITH  
DRY AIR IN PLACE, THIS WILL ONLY PRODUCE MID-LEVEL CLOUDS.  
 
ANOTHER QUIET AND COOL NIGHT IS ON TAP WITH CLEAR SKIES AND LIGHT  
VARIABLE WINDS. CLEAR SKIES AND DRY PROFILES AT THE SURFACE WILL  
SUPPORT COOL TEMPERATURES; LOWS TEMPS WILL DROP INTO THE UPPER 50S.  
THERE WILL BE A CHANCE FOR PATCHY VALLEY FOG AROUND DAYBREAK, BUT  
MINIMAL IMPACT IS EXPECTED.  
   
LONG TERM
 
(TUESDAY THROUGH SUNDAY)  
ISSUED AT 252 AM CDT MON JUL 22 2019  
 
UPPER FLOW PATTERN WILL CONTINUE TO BE DOMINATED BY AN AMPLIFIED  
RIDGE CENTERED OVER THE DESERT SW AND A TROUGH OVER THE NORTHEAST  
U.S./EASTERN CANADA. THIS PATTERN WILL CONTINUE TO BRING DRY, MILD  
AND LESS HUMID AIR MASS AT THE SURFACE. TUESDAY WILL BE ANOTHER NICE  
DAY, BUT TEMPERATURES WILL RUN A BIT WARMER THAN MONDAY WITH HIGHS  
MOSTLY IN THE LOW 80S.  
 
MODELS ARE IN GOOD AGREEMENT SHOWING THE RIDGE BREAKING DOWN BY MID-  
WEEK, BRINGING THE RETURN OF SHOWER AND THUNDERSTORM CHANCES. UPPER  
LEVEL FLOW WILL TRANSITION TO A MORE ZONAL COMPONENT, LEADING TO  
FAST-MOVING RIPPLES AHEAD OF AN UPPER LEVEL TROUGH SLIDING INTO THE  
PACIFIC NORTHWEST. AT THE SURFACE, RETURN FLOW BRINGS LOW TO MID-  
LEVEL MOISTURE BACK, ALONG WITH POSSIBLE SURFACE CONVERGENCE AREAS  
WITH AN APPROACHING SURFACE LOW/COLD FRONT ARRIVING WEDNESDAY NIGHT  
INTO THURSDAY. PRECIPITATION CHANCES CONTINUE INTO THE WEEKEND AS  
THE MAIN UPPER-LEVEL TROUGH MOVES NORTH OF THE FORECAST AREA.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)  
ISSUED AT 1235 PM CDT MON JUL 22 2019  
 
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD.  
 

 
   
FSD WATCHES/WARNINGS/ADVISORIES
 
 
SD...NONE.  
MN...NONE.  
IA...NONE.  
NE...NONE.  

 
 

 
 
SHORT TERM...05  
LONG TERM...05  
AVIATION...  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SD Page
The Nexlab IA Page
The Nexlab MN Page
The Nexlab NE Page Main Text Page