River Flood Warning 10, NWS Des Moines, IA

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
855 PM CST SUN MAR 2 2008

.UPDATED PUBLIC DISCUSSION.

.DISCUSSION...
WILL BE MAKING SOME ADJUSTMENTS TO FFA OVER THE WESTERN SECTIONS OF
THE FORECAST AREA AS RAIN CHANGES OVER TO SNOW/SLEET THERE. SO FAR...
A BRIEF PERIOD OF FZRA HAS ACCOMPANIED THE CHANGEOVER...OTHERWISE
THE TRANSITION HAS PROGRESSED AS EXPECTED. MAJOR CONCERN THIS
EVENING IS THE ANOMALOUS MOISTURE PROFILE IN THE UPPER AIR DATA AND
THE MAIN WAVE YET TO IMPACT THE AREA TONIGHT. QUICK CHECK AT 00Z NAM
SHOWS NEARLY AN INCH OF QPF OVER THE SOUTHEAST TOWARD AM HOURS.
THOUGH A GOOD SHARE OF THIS WILL FALL AS RAIN YET WITH EMBEDDED
THUNDERSTORMS. FLOODING POTENTIAL REMAINS THERE. SNOWFALL TOTALS
WILL BE WATCHED CLOSELY AS UPSTREAM MOISTURE STILL HIGH. NO
ADJUSTMENTS TO TEMPS. WINDS ADJUSTED UP. /REV

.PREVIOUS DISCUSSIONS...
WILL BE ISSUING A FLASH FLOOD WATCH FOR THE SOUTHEAST TWO THIRDS OF
THE FORECAST AREA FOR TONIGHT. ALONG WITH VERY WARM TEMPS TODAY...
SIGNIFICANT MELTING HAS OCCURRED LEADING TO RAPID RUNOFF.  WITH
TEMPS CRASHING TONIGHT...PROBLEMS WILL LESSEN...BUT PERIOD OF
POTENTIAL .25 TO .50 WIDESPREAD RAINFALL ON TOP OF ALREADY REPORTS
OF FLOODING AND RUNOFF WILL CAUSE ADDITIONAL ISSUES. ONCE CHANGEOVER
OCCURS...STILL LOOKING FOR SNOW/SLEET AND COLD. BY MORNING...RUNOFF
WILL HAVE ENDED DUE TO FREEZING TEMPS ONCE AGAIN./REV

SURFACE LOW PRESSURE OVER WEST CENTRAL IOWA WITH WARM FRONT
EXTENDING EASTWARD THROUGH CENTRAL AND SOUTHEAST IOWA AND A COLD
FRONT EXTENDING TO THE SOUTH. TEMPERATURES HAVE BECOME QUITE MILD IN
THE WARM SECTOR WITH READINGS IN THE LOW TO MID 60S AND DEWPOINTS
PUSHING INTO THE 50S. AIRMASS BEGINNING TO BECOME UNSTABLE IN THE
WARM SECTOR AHEAD OF THE COLD FRONT. GOOD CONVERGENCE IS EXPECTED
NEAR THE COLD FRONT AS IS SWINGS SOUTHEAST THIS AFTERNOON AND EARLY
EVENING. THIS SHOULD BE ENOUGH TO SPARK OFF A FEW THUNDERSTORMS OVER
SOUTH CENTRAL IOWA WITH A FEW POSSIBLY BECOMING SEVERE. INCREASING
CLOUDS AND A LINGERING SNOW FIELD MAY LIMIT THE POTENTIAL TO A
DEGREE.

THE PRIMARY FOCUS FOR THE FORECAST WILL BE TONIGHT WHEN THE BULK OF
THE PRECIPITATION IS EXPECTED TO OCCUR. BESIDES THE SFC COLD
ADVECTION ASSOCIATED WITH THE COLD FRONT...THE PRIMARY COLD
ADVECTION OCCURS FROM 900-925 MB WITH A WARM LAYER REMAINING ABOVE
THIS FOR SEVERAL MORE HOURS. THIS WILL CREATE PRECIPITATION TYPE
CONCERNS DURING THE PERIOD WITH A TRANSITION FROM RAIN TO SLEET TO
SNOW EXPECTED FROM NORTHWEST TO SOUTHEAST. FREEZING RAIN IS NOT A
PRIMARY CONCERN AT THE MOMENT FOR A COUPLE OF REASONS. FIRST THE
MILD TEMPERATURES TODAY HAVE WARM GROUND TEMPERATURES AND SECOND ARE
SURFACE TEMPERATURES WILL LIKELY BE AT OR ABOVE FREEZING PRIOR TO
THE TRANSITION TO SLEET AND SNOW. ANY PRECIPITATION THAT DOES OCCUR
WILL BE CONVECTIVE DURING MUCH OF THE EVENT. DESPITE THIS...DO NOT
EXPECT WARNING CRITERIA WINTER PRECIPITATION TO OCCUR DUE TO THE
PROGRESSIVE NATURE OF THE SYSTEM AND THE DELAY OF TRANSITION TO
SNOW. THE TRANSITION TIMEFRAME TO ALL SNOW LOOKS TO BE AROUND
MIDNIGHT FROM WATERLOO TO DES MOINES TO CORNING.

A COLD AND BREEZY MONDAY CAN BE EXPECTED IN THE WAKE OF THE SYSTEM
WITH LIGHT SNOW LINGERING EARLY OVER THE FAR SOUTHEAST. THE UPPER
LOW PASSING TO THE SOUTHEAST AND THROUGH THE LOWER MISSISSIPPI
VALLEY IS FORECAST TO REMAIN JUST FAR ENOUGH SOUTH TO NOT AFFECT THE
AREA THOUGH CONTINUES TO LOOK LIKE A PRIME SEVERE WEATHER PRODUCER
THROUGH THE SOUTHERN PLAINS. A CLIPPER DROPS SOUTHEAST THROUGH THE
NORTHWEST FLOW TUESDAY NIGHT AND WEDNESDAY AND WILL BRING LOW
CHANCES FOR SNOW. THE NEXT WAVE OF COLD AIR TO DROP SOUTH WILL MOVE
THROUGH LATE THURSDAY AND THURSDAY NIGHT WITH THE LONG WAVE TROUGH
SETTLING INTO THE CENTRAL AND NORTHERN PLAINS. IT WILL BE QUITE COOL
ON FRIDAY BEFORE A WARMING TREND FOR THE WEEKEND WITH A TRANSITION
TO ZONAL FLOW.

&&

.HYDROLOGY...
WILL BE ISSUING A FLASH FLOOD WATCH FOR PORTIONS OF THE AREA TONIGHT
DUE TO CONTINUED RUNOFF PROBLEM AND HEAVY RAINFALL ENTERING THE
WESTERN AREAS OF THE STATE ATTM. BASINS BETWEEN DSM AND OTM HAVE
SNOW WATER EQUIVALENTS OF 2-4 INCHES BASED ON NOHRSC ESTIMATES THIS
MORNING AND HAS GREATLY DECREASED WITH ACCELERATED MELTING TODAY.
SOME ICE JAMMING IS EXPECTED IN ADDITION TO SNOW MELT RISES AND
EXPECTED RAINFALL THIS EVENING. WILL CONTINUE MENTION IN THE HWO
REGARDING CHARITON...S SKUNK AND DES RIVER TRIBS IN THESE AREAS.
COULD BE PLENTY OF STANDING WATER TOO THAT HAS DIFFICULTY DRAINING
DUE TO FULL SNOWPACKED DITCHES.

&&

.AVIATION...03/00Z
LITTLE TIME FOR DISCUSSION...HAVE LET 18Z PACKAGE RIDE AS IT IS
LOOKING GOOD FOR NOW.  WILL BE TWEAKING PACKAGE ALONG THE WAY
TONIGHT AS THUNDER ENDS SOUTHEAST AND RA/SN GIVES WAY TO SNOW AND
WIND LATER THIS EVENING....PREVIOUS DISCUSSION...LOTS OF LOW LEVEL
MOISTURE IS STREAMING NORTH AHEAD OF COLD FRONT...BUT IT IS SHALLOW.
AFTER LONG TRACK OVER MELTING SNOW ...IT IS PRODUCING LOW CLOUDS AND
FOG IN NRN IA...WITH IFR CONDITIONS. DRIZZLE AND LIGHT RAIN ARE
EXPECTED TO DEVELOP THROUGH THE AFTERNOON INTO EARLY EVENING...
PROLONGING IFR IN NORTH. FARTH S...SHOWERS OR THUNDERSTORMS ARE
EXPECTED TO DEVELOPED SE OF KDSM...WITH MVFR ASSOCIATED. AFTER THE
FRONT...MAINLY 03Z-09Z A BAND OF SNOW WILL SPREAD EWD ACROSS CENTRAL
IA PRODUCING IFR CIGS AND VISIBILITIES. MVFR FOLLOWING THEN CLEARING
MON MORNING.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...

FLASH FLOOD WATCH UNTIL 12Z-HAMILTON-HARDIN-GRUNDY-BLACK HAWK
-BOONE-STORY-MARSHALL-TAMA-DALLAS-POLK-JASPER-POWESHIEK-MADISON
-WARREN-MARION-MAHASKA-UNION-CLARKE-LUCAS-MONROE-WAPELLO-RINGGOLD
-DECATUR-WAYNE-APPANOOSE-DAVIS-

WINTER WX ADVY UNTIL 12Z -CERRO GORDO-WRIGHT-FRANKLIN-
CALHOUN-WEBSTER-HAMILTON-CRAWFORD-CARROLL-GREENE-
BOONE-AUDUBON-GUTHRIE-

WINTER WX ADVY UNTIL 12Z  -BLACK HAWK-BUTLER-
BREMER-HARDIN-GRUNDY-STORY-MARSHALL-DALLAS-POLK-CASS-ADAIR-
MADISON-ADAMS-UNION-TAYLOR-

WINTER WX ADVY TONIGHT 06Z-15Z-
TAMA-JASPER-POWESHIEK-MARION-MAHASKA-CLARKE-LUCAS-MONROE-WAPELLO-
RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS-

&&

AVIATION...REV
SHORT TERM...REV
LONG TERM...DONAVON

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
630 PM CST SUN MAR 2 2008

IAZ004>007-015-016-023-024-033-031100-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-POCAHONTAS-
HUMBOLDT-SAC-
630 PM CST SUN MAR 2 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL AND
NORTHWEST IOWA.

.DAY ONE...TONIGHT

LIGHT RAIN WILL CHANGE TO LIGHT SNOW. ACCUMULATIONS SHOULD VARY FROM
A DUSTING TO TWO INCHES BEFORE THE PRECIPITATION ENDS AFTER
MIDNIGHT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

IAZ017-025>028-034>038-044>049-057>060-070>072-081-082-092-031100-
CERRO GORDO-WRIGHT-FRANKLIN-BUTLER-BREMER-CALHOUN-WEBSTER-
HAMILTON-HARDIN-GRUNDY-CRAWFORD-CARROLL-GREENE-BOONE-STORY-
MARSHALL-AUDUBON-GUTHRIE-DALLAS-POLK-CASS-ADAIR-MADISON-ADAMS-
UNION-TAYLOR-
630 PM CST SUN MAR 2 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST...CENTRAL
AND NORTHEAST IOWA.

.DAY ONE...TONIGHT

RAIN DURING THE LATE AFTERNOON WILL MIX WITH SLEET...AND THEN CHANGE
TO ALL SNOW THIS EVENING. ACCUMULATIONS SHOULD VARY FROM TWO TO FOUR
INCHES...BUT LOCALLY HIGHER AMOUNTS ARE POSSIBLE. MOST OF THE SNOW
WILL FALL IN JUST A FEW HOURS.  WITH BRISK NORTHWEST WINDS AT SPEEDS
OF 15 TO 30 MPH...VISIBILITIES MAY BE REDUCED TO A HALF MILE OR LESS
DURING THE PERIODS OF MORE INTENSE SNOW.

IN ADDITION...RAPID SNOW MELT TODAY HAS CAUSED RISES IN RIVERS...
STREAMS...AND RUN OFF FROM FIELDS OVER GRAVEL AND PAVED ROADS.
FLOODING HAS OCCURRED IN SOME AREAS AND IS EXPECTED TO CONTINUE INTO
THE EVENING HOURS.

A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE AREA. A FLASH FLOOD
WATCH IS IN EFFECT FOR PARTS OF THE OUTLOOK AREA. FLOOD WARNINGS ARE
IN EFFECT FOR PORTIONS OF THE AREA. PLEASE REFER TO THE NATIONAL
WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR MORE DETAILS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED...SNOWFALL REPORTS ARE
APPRECIATED.  ANY REPORTS OF ROAD OR FIELD FLOODING SHOULD BE
RELAYED TO LOCAL LAW ENFORCEMENT OR THE NATIONAL WEATHER SERVICE.

IAZ039-050-061-062-073>075-083>086-093>097-031100-
BLACK
HAWK-TAMA-JASPER-POWESHIEK-WARREN-MARION-MAHASKA-CLARKE-LUCAS-MONROE-
WAPELLO-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS-
630 PM CST SUN MAR 2 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN AND
EASTERN IOWA.

.DAY ONE...TONIGHT

FOR AREAS SOUTH OF I-80...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE
THIS EVENING...WITH POTENTIAL FOR DAMAGING WINDS OR LARGE HAIL.

LATER IN THE EVENING...RAIN WILL MIX WITH SLEET AND SNOW...AND THEN
CHANGE TO ALL SNOW AFTER MIDNIGHT. ACCUMULATIONS SHOULD VARY FROM
ONE TO TWO INCHES...BUT LOCALLY HIGHER AMOUNTS MAY OCCUR. MOST OF
THE SNOW WILL FALL IN JUST A FEW HOURS...REDUCING VISIBILITY AND
CAUSING SLICK CONDITIONS.

IN ADDITION...WARM TEMPERATURES AGAIN TODAY ARE CAUSING SNOW
MELT...SO SMALL STREAMS AND TRIBUTARIES MAY REACH BANK FULL.
LOCALIZED FLOODING MAY OCCUR DUE TO RUN OFF OF WATER OVER GRAVEL
AND PAVED ROADS.

A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE AREA. A FLASH FLOOD
WATCH IS IN EFFECT FOR PARTS OF THE AREA. RIVER FLOOD WARNINGS ARE
ALSO IN EFFECT FOR PORTIONS OF THE AREA. PLEASE REFER TO THE
NATIONAL WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR MORE
DETAILS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING...AND SNOWFALL REPORTS
ARE ALWAYS APPRECIATED AND ENCOURAGED. ANY REPORTS OF ROAD OR FIELD
FLOODING SHOULD BE RELAYED TO LOCAL LAW ENFORCEMENT OR THE NATIONAL
WEATHER SERVICE.

JUNGBLUTH/REV

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
635 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0622 PM     FLASH FLOOD      5 E COLO                42.02N 93.22W
03/02/2008                   MARSHALL           IA   EMERGENCY MNGR

            WATER FLOWING OVER HIGHWAY 30.

&&

CCOGIL

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
637 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0425 PM     FLASH FLOOD      5 E COLO                42.02N 93.22W
03/02/2008                   MARSHALL           IA   EMERGENCY MNGR

            WATER FLOWING OVER HIGHWAY 30. ALSO WATER FLOWING OVER
            HIGHWAY 65 NEAR ZEARING AND JUST SOUTH OF COLO. NUMEROUS
            COUNTY ROADS HAVE WATER OVER THEM.

&&

CCOGIL

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
640 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0629 PM     FLASH FLOOD      OTTUMWA                 41.02N 92.42W
03/02/2008                   WAPELLO            IA   TRAINED SPOTTER

            AT LEAST 3 INCHES OF WATER IN SPOTTERS BASEMENT...ALONG
            WITH SEVERAL OTHER HOMES IN OTTUMWA NEIGHBORHOOD TAKING
            WATER IN BASEMENTS.

&&

PODRAZIK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
743 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0737 PM     SNOW             JEFFERSON               42.02N 94.38W
03/02/2008  E1.0 INCH        GREENE             IA   LAW ENFORCEMENT

            A HALF TO ONE INCH OF SLEET AND SNOW MIX.

&&

PODRAZIK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
747 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0716 PM     SNOW             DANA                    42.11N 94.24W
03/02/2008  E1.5 INCH        GREENE             IA   BROADCAST MEDIA

            AN INCH TO 1.5 INCHES OF SLEET AND SNOW MIX. FROM WOI TV.

&&

PODRAZIK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
813 PM CST SUN MAR 02 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0750 PM     FLASH FLOOD      OTTUMWA                 41.02N 92.42W
03/02/2008                   WAPELLO            IA   LAW ENFORCEMENT

            WILDWOOD ROAD IN OTTUMWA CLOSED FROM HIGH WATER. NUMEROUS
            OTHER GRAVEL ROADS IN COUNTY CLOSED DUE TO WATER RUNNING
            OVER THEM OR FROM WASHOUTS.

&&

CCOGIL