000
FXUS63 KDMX 251150
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
650 AM CDT SAT MAY 25 2013

.SHORT TERM.../TODAY/...
ISSUED AT 332 AM CDT SAT MAY 25 2013

STRONG MOISTURE TRANSPORT FEEDING THE COMPLEX IN NEBRASKA THIS
MORNING WILL TRANSLATE EAST AS WINDS VEER SOMEWHAT TOWARD SUNRISE.
IT APPEARS THE STRONGEST ACTIVITY IS PUNCHING SOUTH WITH THE CORFIDI
VECTORS...BUT PLENTY OF RECENT DEVELOPMENT INTO WEST CENTRAL IA.
HEAVIEST RAIN SHOULD BE OVER THE SOUTH TWO THIRDS OF THE CWA...WITH
MUCH OF IT FALLING IN THE MORNING.  SHOULD SEE THE PRECIP BECOME MORE
SCATTERED FOR THE AFTERNOON.  RAIN MAKES FOR A TRICKY FORECAST FOR A
COUPLE REASONS.  ONE BEING THE PERSISTENT RAIN WILL KEEP TEMPS
DOWN.  THE OTHER IS THE DRY AIR AT LOW LEVELS FEEDING INTO EASTERN
IA.  DEW POINTS IN THE MID 30S COMBINED WITH THE TSRA GOING OVER THE
TOP TO TRY TO SATURATE THE LOW LEVELS SUGGESTS THERE MAY BE VERY
LITTLE RISE FROM THE CURRENT READINGS.  NON-DIURNAL TRACE OVER THE
CWA WITH MAX TEMPS REACHED LATE IN THE PERIOD.

.LONG TERM.../TONIGHT THROUGH FRIDAY/...
ISSUED AT 332 AM CDT SAT MAY 25 2013

NEARLY CONTINUOUS POPS THROUGH FORECAST AS SOUTH/SOUTHWESTERLY FLOW
PERSISTS ACROSS AREA WITH MULTIPLE SYSTEMS PASSING ACROSS REGION.
FOR BEGINNING OF PERIOD DO NOT HAVE HIGH CONFIDENCE IN LOCATION OF
POPS...AS ONGOING MCS ACROSS NEBRASKA WILL INFLUENCE LOCATION OF
OVERNIGHT DEVELOPMENT. MCS CURRENTLY LOOKS TO TRACK A BIT FURTHER
SOUTH THAN ORIGINALLY ANTICIPATED...AND OUTFLOW BOUNDARY MAY LINGER
INTO KANSAS/MISSOURI WITH THAT BECOMING FOCUS FOR OVERNIGHT
DEVELOPMENT TONIGHT. HOWEVER...MODELS CONTINUE TO DEVELOP PRECIP
NEAR A BOUNDARY WITH GOOD THETA-E ADVECTION NEAR THE MISSOURI
RIVER VALLEY...LIFTING SLIGHTLY TO THE NORTHEAST OVERNIGHT. HAVE
TRENDED TOWARDS THIS SOLUTION...WITH AT LEAST SCATTERED
PRECIPITATION LIKELY ALONG THIS REGION. HOWEVER...HIGHEST
PRECIPITATION MAY AGAIN BE SOUTH OF THE AREA. SYSTEM WILL CONTINUE
TO PULL EASTWARD THROUGHOUT THE DAY SUNDAY...WITH ADDITIONAL
DEVELOPMENT AGAIN POSSIBLE MONDAY NIGHT BEHIND BOUNDARY AS A SHORT
WAVE PUSHES EAST. AGAIN...PREVIOUS NIGHTS CONVECTION WILL
INFLUENCE LOCATION OF SUNDAY NIGHT PRECIPITATION. SYSTEM WILL
CONTINUE TO LIFT ACROSS NORTHERN IOWA THROUGH THE DAY MONDAY. WILL
LIKELY SEE BREAKS IN PRECIPITATION FOR THE AFTERNOON SUNDAY AND
AGAIN MONDAY...ESPECIALLY ACROSS THE WEST. HOWEVER...AN AREA OF
LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY WILL CONTINUE TO
INFLUENCE WEATHER ACROSS IOWA WITH ANOTHER BOUNDARY LIFTING NORTH
THROUGH THE AREA FOR MONDAY NIGHT INTO TUESDAY...WITH AGAIN...GOOD
CHANCE FOR PRECIPITATION ALONG BOUNDARY. AS SYSTEM CONTINUES TO
LIFT NORTH...WILL SEE LINGERING PRECIPITATION ALONG THE BOUNDARY
THROUGH MUCH OF THE REMAINDER OF THE PERIOD...BEFORE YET ANOTHER
LOW PUSHES THROUGH FOR THE END OF THE WEEK BRINGING CONTINUED
PRECIPITATION CHANCES. WHILE POPS ARE IN NEARLY EVERY
PERIOD...WITH SEE BREAKS IN PRECIPITATION...ESPECIALLY DURING THE
LATE MORNING AND EARLY AFTERNOON HOURS...AND BEST CHANCES FOR DRY
WEATHER ACROSS THE SOUTH MID WEEK WITH SYSTEM TO THE NORTH.

PWAT VALUES REMAIN VERY HIGH FOR LATE MAY...REACHING 1.5 IN OR
GREATER...AND GOOD CLOUD DEPTHS WOULD ALLOW FOR VERY EFFICIENT
RAINFALL RATES. IF STORMS TRAIN OVER AN AREA MAY SEE FLASH
FLOODING...HOWEVER...ANTICIAPTE FAIRLY PROGRESSIVE NATURE TO
SYSTEMS AND HAVE NOT ISSUED FLASH FLOOD WATCH...THOUGH ONE MAY BE
NEEDED IN AREAS WHERE HEAVY RAINFALL OCCURS OVERNIGHT.

MODELS CONTINUE TO KEEP TEMPERATURES COOLER WITH ONGOING
PRECIPITATION...AND HAVE LOWERED TEMPERATURES A BIT FOR THE NEAR
TERM. HOWEVER...ANTICIPATE TEMPERATES TO WARM THROUGH THE
PERIOD WITH WAA AND SOUTHWESTERLY FLOW RETURNING MID WEEK.

&&

.AVIATION...25/12Z
 ISSUED AT 640 AM CDT SAT MAY 25 2013

MCC MOVING ACROSS THE STATE THIS MORNING WILL SATURATE THE LOW
LEVELS OF OF THE ATMOSPHERE...RESULTING IN DETERIORATING
CONDITIONS. THE THUNDER THREAT WILL TAPER OFF BY AROUND 15Z OR SO
WITH SCATTERED SHOWERS AND INCREASING AREAS OF CIGS BLO 010.
ADDITIONAL TSRA DEVELOPMENT TONIGHT WITH WIDESPREAD IFR CIGS.

&&

.HYDROLOGY...
ISSUED AT 640 AM CDT SAT MAY 25 2013

MORNING MCC COMING OUT OF NEBRASKA IS SETTING THE STAGE FOR
POTENTIAL FLOODING CONDITIONS WITH FURTHER RAINFALL. FFG VALUES
WERE GENERALLY IN THE 2 TO 2.25 INCH RANGE IN MOST AREAS...WITH
SOME A LITTLE UNDER 2 INCHES IN THE CENTRAL AND NERN COUNTIES. THE
SYSTEM THIS MORNING IS MOVING ALONG...BUT LEAVING SOME INCH PLUS
RAINFALL AMOUNTS. THOUGH DO NOT EXPECT TO SEE A FLOODING PROBLEM
WITH THIS MORNINGS RAIN...HOWEVER EACH ROUND WILL BRING AN
ENHANCED CHANCE FOR FLOODING AS GROUND BECOMES MORE SATURATED.
MANY UNCERTAINTIES...NOT THE LEAST OF WHICH IS WHERE THE FINAL
BOUNDARY WILL SET UP FROM THIS MORNINGS ACTIVITY. THINKING AT THIS
TIME IS THE BEST CHANCE FOR SIG RAINFALL MAY BE TO THE SOUTH OF
THE CWA FOR TONIGHT AS COOL POOL SHOULD BE QUITE STRONG AND KEEP
THE FRONTAL CONVERGENCE TO THE SOUTH. THIS WILL NEED TO BE
MONITORED TODAY WITH THE POTENTIAL FOR HEADLINES IN THE AFTERNOON
PACKAGE.

&&

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

$$

SHORT TERM...MS MAY 13
LONG TERM...AWB
AVIATION...MS MAY 13
HYDROLOGY...MS MAY 13