National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KDMX 301737
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
1237 PM CDT WED JUL 30 2014

.SHORT TERM /TODAY/...
ISSUED AT 327 AM CDT WED JUL 30 2014

TEMPS AND HOW TO DEAL WITH PRECIP POTENTIAL REMAIN THE PRIMARY
CONCERNS TODAY. IA REMAINS BETWEEN INFLUENCES OF BROAD CYCLONIC FLOW
OF HUDSON BAY UPPER LOW...AND FORCING ASSOCIATED WITH RIGHT ENTRANCE
REGION OF NW-SE IA JET SEGMENT WITH SHORT WAVES DRIFTING OVER WRN
CONUS RIDGE THROUGH THE ROCKIES. AIRMASS IS MORE THERMODYNAMICALLY
FAVORABLE FOR PRECIP SW AND NE OF IOWA...ESPECIALLY SW...SO ANY
POTENTIAL LOCALLY IS MINIMAL. OUR SCENARIO WILL BE VERY SIMILAR TO
YESTERDAY...DRIVEN BY SHALLOW WEAK INSTABILITY WITH LITTLE LOW LEVEL
FOCUS OR CONVERGENCE. AREAL COVERAGE OF ANYTHING THAT FORMS WOULD BE
VERY MINIMAL...WELL UNDER 10 PERCENT. THUS WILL KEEP SILENT MENTION
AND FORECAST DRY OUTSIDE OF FAR NE CORNER CLOSER TO BETTER MLCAPES.
EXPECT SCATTERED SHOWERS TOWARD THE GREAT LAKES...SIMILAR TO
YESTERDAY...POSSIBLY JUST CLIPPING MASON CITY AND/OR WATERLOO AREAS
BUT CHANCES ARE STILL NOT GREAT AND RELEGATED TO SLIGHTS. 0-2KM
TEMPS CONTINUE TO NUDGE UP JUST SLIGHTLY DAY TO DAY SO HAVE ADDED A
DEGREE OR TWO TO PERSISTENCE FOR HIGHS.

.LONG TERM /TONIGHT THROUGH MONDAY/...
ISSUED AT 327 AM CDT WED JUL 30 2014

LITTLE CHANGE IN OVERALL THINKING FOR THE LONG TERM FORECAST
TONIGHT...WITH THE REST OF THIS WEEK DOMINATED BY A DEEP TROUGH
ACROSS THE EASTERN HALF OF THE U.S. RESULTING IN MILD AND QUIET
WEATHER ACROSS IOWA. HAVE HELD POPS OUT OF MOST PERIODS DESPITE
THE POTENTIAL FOR A FEW SMALL SHOWERS AT TIMES...AS THE COVERAGE
WOULD BE VERY LOW AND THE IMPACTS ESSENTIALLY NIL. THE MOST LIKELY
PERIODS FOR RAIN WILL BE AROUND LATE THURSDAY AND FRIDAY...BUT
EVEN THEN POPS ARE HELD AT 10 TO 20 PERCENT DUE TO THE EXPECTED
LOW COVERAGE. MEANWHILE HAVE CONTINUED TREND OF WARMING MAX TEMPS
BY A DEGREE OR SO EACH DAY AS THE AIRMASS SLOWLY MODIFIES BUT ALL
IN ALL THE SENSIBLE WEATHER WILL BE PRETTY STEADY STATE FOR THE
REMAINDER OF THIS WEEK.

BY THE MIDDLE OF THE WEEKEND THE EASTERN U.S. TROUGH WILL FINALLY
BE MOVING AWAY AND THE WESTERN U.S. RIDGE WILL BE REASSEMBLING
ITSELF OVER THE ROCKIES...WITH IOWA LYING NEAR THE NORTHEASTERN
PERIPHERY OF THE RIDGE AND CLOSE TO THE PROVERBIAL RING OF FIRE.
DURING THE FIRST HALF OF NEXT WEEK THIS WILL LIKELY RESULT IN A
SOMEWHAT MORE ACTIVE WEATHER PATTERN...DEPENDING ON HOW STRONG THE
RIDGE IS AND WHERE THE ASSOCIATED ZONE OF RAINFALL SETS UP...WITH
TEMPERATURES A BIT WARMER AND A RETURN OF MORE SIGNIFICANT
RAINFALL CHANCES AROUND OR JUST BEYOND THE END OF THE CURRENT
SEVEN DAY FORECAST PERIOD.

&&

.AVIATION...30/18Z
ISSUED AT 1237 PM CDT WED JUL 30 2014

CU FIELD FILLING IN THIS AFTERNOON. BUFR SOUNDINGS AND LAPSE RATES
STILL SUGGEST POSSIBLE ISOLATED SHOWERS NORTHEAST...BUT COVERAGE
NOT HIGH ENOUGH TO ADD TO PACKAGE AT THIS TIME. WILL MONITOR...ANY
THAT DO DEVELOP WOULD BE ABOUT 20-00Z. AFTER THAT SKIES CLEAR AND
LIGHT WINDS REMAIN WITH RETURN CU FIELD AFT 15Z THURSDAY...SCT AT
FIRST AND BECOMING SCT/BKN VFR AFT 18Z./REV

&&

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

$$

SHORT TERM...SMALL
LONG TERM...LEE
AVIATION...REV