Area Forecast Discussion
Issued by NWS Des Moines, IA

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KDMX 082345
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
645 PM CDT TUE JUL 8 2014

.SHORT TERM /TONIGHT/...
ISSUED AT 328 PM CDT TUE JUL 8 2014

QUIET WEATHER EXPECTED OVERNIGHT WITH QUICK DECOUPLING THIS
EVENING ALLOWING WINDS TO DIE OFF TOWARD SUNSET. CU FIELD WILL
ALSO DISSIPATE AS DAYTIME HEATING SUBSIDES WITH CLEAR SKIES AND
LIGHT WINDS OVERNIGHT. TEMPERATURES WILL BE BELOW NORMAL OVERNIGHT
WITH CANADIAN RIDGE SLIDING INTO THE MISSOURI RIVER VALLEY. HAVE
GENERALLY GONE AT OR BELOW GUIDANCE...ESPECIALLY IN FAVORED AREAS
OF NISHNA VALLEYS IN THE WEST AND THE NORTH.

.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
ISSUED AT 328 PM CDT TUE JUL 8 2014

MAIN FORECAST CONCERN DEALT WITH THUNDERSTORM CHANCES THURSDAY
NIGHT INTO FRIDAY AND AGAIN ON SATURDAY. LEANED TOWARD A BLEND OF
NAM/GFS/ECMWF THROUGH FRIDAY...THEN TOWARDS GFS FROM THE WEEKEND
INTO NEXT WEEK.

WEDNESDAY THROUGH FRIDAY...CANADIAN HIGH PRESSURE WILL CONTINUE TO
PROVIDE SLIGHTLY BELOW NORMAL TEMPERATURES AND MOSTLY CLEAR
SKIES THROUGH THURSDAY. MODELS HINTING ON A WEAK 500MB SHORTWAVE
TO CUT ACROSS THE NORTHEAST PORTION OF THE STATE ON WEDNESDAY
AFTERNOON...BUT FORECAST SOUNDINGS SUGGEST ANYTHING THAT DEVELOPS
WOULD BE ELEVATED AND WOULD HAVE TO FIGHT A LARGE DRY LAYER TO
REACH THE SURFACE. PLUS WITH LIMITED DEEPER MOISTURE AND FORCING
AVAILABLE...CONFIDENT TO LEAVE FORECAST DRY ATTM ON WEDNESDAY.

CUTBACK ON POPS ON THURSDAY PRIOR TO 00Z FRIDAY AS MODELS
CONTINUE TO SLOW DOWN SYSTEM LATE IN THE WEEK. MOISTURE TRANSPORT
AND THETA-E ADVECTION INCREASE THURSDAY EVENING INTO FRIDAY AHEAD
NEXT SURFACE LOW TO DEVELOP OVER THE WESTERN PLAINS. A 500MB
TROUGH LOOKS TO MOVE ACROSS THE STATE OVERNIGHT THURSDAY NIGHT
THROUGH FRIDAY MORNING AND HAVE HIGHEST POPS GOING DURING THIS
TIME. WITH THE SLOWER MODEL SOLUTIONS...KEPT LIKELY POPS ACROSS
THE EAST ON FRIDAY.

SATURDAY THROUGH TUESDAY...BOUNDARY LOOKS TO STALL OUT ACROSS
CENTRAL TO SOUTHERN IOWA DURING THE WEEKEND AND WITH VARIOUS WEAK
UPPER LEVEL SHORTWAVES MOVING ACROSS THE REGION...TIMING OF POPS
BECOMES TRICKY WITH THIS SCENARIO. CONFIDENT ENOUGH TO TRIM BACK
POPS FRIDAY NIGHT IN THE WEST TO NORTH WITH SOME WEAK RIDGING.
HOWEVER...WITH THE INCREASING MOISTURE AND INSTABILITY DURING THE
WEEKEND...HAVE CHANCE POPS GOING THROUGHOUT THE DAY SATURDAY AND
SATURDAY NIGHT AND THEN SLIGHTLY POPS ON SUNDAY. HIGH PRESSURE BY
EARLY NEXT WEEK PROVIDES ANOTHER DRY PERIOD THROUGH TUESDAY.

&&

.AVIATION...09/00Z
ISSUED AT 640 PM CDT TUE JUL 8 2014

MINOR CONCERNS THIS PERIOD. FEW CUMULUS THIS EVENING WILL
DISSIPATE IN THE NEXT FEW HOURS NORTH CENTRAL AND WINDS REMAIN
LIGHT. LOOKING UPSTREAM...LARGE PLUME OF SMOKE FROM CANADIAN
FOREST FIRES FROM THE NORTHWEST TERRITORIES CURRENTLY SPILLING
ACROSS THE NORTHERN PLAINS...STRETCHING INTO SOUTHERN SOUTH DAKOTA
ALREADY. VSBY DROPPING DUE TO SMOKE AND HAZE ACROSS PORTIONS OF
NORTH DAKOTA. H700 RIDGE EXPECTED TO BUILD SLIGHTLY TONIGHT AND
MAY CONTINUE TRAJECTORY TO PUSH SMOKE ACROSS REGION BY 15-19Z WED.
HAVE INTRODUCED 6SM HZ OVER WESTERN AND SOUTHERN TAF SITES FROM
17Z TO 20Z AS A PRECAUTION. OTHERWISE...LIMITED MIXING AND
GENERALLY VFR CONDITIONS EXPECTED. /REV

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...COGIL
LONG TERM...PODRAZIK
AVIATION...REV


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.