Alert archive / Iowa / Winter Storm Watches in 2012
Winter Storm Watch 3, NWS Des Moines, IA
NWS Des Moines, IA issued this winter storm watch at Dec 17, 2012, 4:01 PM CST for 42 counties in Iowa. It took effect at Dec 19, 2012, 12:00 PM CST. It was in force for .
The area
The counties it named.
The facts
- Issued
- Dec 17, 2012, 4:01 PM CST (22:01 UTC)
- In effect from
- Dec 19, 2012, 12:00 PM CST
- Expired
- Dec 18, 2012, 3:24 PM CST
- In force
- Issued by
- NWS Des Moines, IA
All 42 counties
Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Clarke County, IA, Crawford County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Franklin County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Sac County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Wright County, IA
The radar
The Des Moines radar (KDMX), 7 km from the middle of the area, began a volume at 22:03 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 10.0 hours before the alert went out and 229 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 650 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 97 m²/s²
- 0-3 km storm-relative helicity
- 106 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
113 WWUS43 KDMX 172201 WSWDMX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DES MOINES IA 401 PM CST MON DEC 17 2012 ...FIRST MAJOR WINTER STORM TO AFFECT CENTRAL IOWA MIDWEEK... .STRONG LOW PRESSURE WILL MOVE FROM COLORADO INTO THE OKLAHOMA PANHANDLE ON WEDNESDAY BEFORE LIFTING NORTHEAST INTO ILLINOIS BY THURSDAY. RAIN AND SNOW IS EXPECTED TO OVERSPREAD IOWA ON WEDNESDAY BECOMING ALL SNOW WEDNESDAY NIGHT AND ENDING THURSDAY. VERY STRONG NORTHWEST WINDS WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING SNOW LATE WEDNESDAY NIGHT INTO THURSDAY. IAZ025>028-033>039-044>050-057>062-070>075-081>086-092>097-180600- /O.NEW.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN- GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE-BOONE-STORY-MARSHALL- TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR- MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE- WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS- INCLUDING THE CITIES OF...CLARION...HAMPTON...ALLISON...WAVERLY... SAC CITY...ROCKWELL CITY...FORT DODGE...WEBSTER CITY...ELDORA... GRUNDY CENTER...WATERLOO...DENISON...CARROLL...JEFFERSON... BOONE...AMES...MARSHALLTOWN...TOLEDO...AUDUBON...GUTHRIE CENTER... ADEL...DES MOINES...NEWTON...GRINNELL...ATLANTIC...GREENFIELD... WINTERSET...INDIANOLA...KNOXVILLE...OSKALOOSA...CORNING... CRESTON...OSCEOLA...CHARITON...ALBIA...OTTUMWA...BEDFORD... MOUNT AYR...LEON...CORYDON...CENTERVILLE...BLOOMFIELD 401 PM CST MON DEC 17 2012 ...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON. * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA ON WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW ON WEDNESDAY NIGHT BEFORE ENDING ON THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...5 TO 8 INCHES OF SNOW IS EXPECTED IN THE WATCH AREA. LOCAL AMOUNTS OF UP TO 10 INCHES WILL BE POSSIBLE. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG ON WEDNESDAY NIGHT FROM THE NORTH TO NORTHWEST. SUSTAINED WINDS OF 20 TO 30 MPH ARE EXPECTED WITH GUSTS OVER 35 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED AROUND DAYBREAK ON THURSDAY WITH NEAR BLIZZARD CONDITIONS POSSIBLE WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL. CONTINUE TO MONITOR THE LATEST FORECASTS. && $$
4 follow-up statements
233 WWUS43 KDMX 180253 WSWDMX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DES MOINES IA 853 PM CST MON DEC 17 2012 ...FIRST MAJOR WINTER STORM TO AFFECT CENTRAL IOWA MIDWEEK... .STRONG LOW PRESSURE WILL MOVE FROM COLORADO INTO THE OKLAHOMA PANHANDLE ON WEDNESDAY BEFORE LIFTING NORTHEAST INTO ILLINOIS BY THURSDAY. RAIN AND SNOW IS EXPECTED TO OVERSPREAD IOWA ON WEDNESDAY BECOMING ALL SNOW WEDNESDAY NIGHT AND ENDING THURSDAY. VERY STRONG NORTHWEST WINDS WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING SNOW LATE WEDNESDAY NIGHT INTO THURSDAY. IAZ025>028-033>039-044>050-057>062-070>075-081>086-092>097-181100- /O.CON.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN- GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE-BOONE-STORY-MARSHALL- TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR- MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE- WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS- INCLUDING THE CITIES OF...CLARION...HAMPTON...ALLISON...WAVERLY... SAC CITY...ROCKWELL CITY...FORT DODGE...WEBSTER CITY...ELDORA... GRUNDY CENTER...WATERLOO...DENISON...CARROLL...JEFFERSON... BOONE...AMES...MARSHALLTOWN...TOLEDO...AUDUBON...GUTHRIE CENTER... ADEL...DES MOINES...NEWTON...GRINNELL...ATLANTIC...GREENFIELD... WINTERSET...INDIANOLA...KNOXVILLE...OSKALOOSA...CORNING... CRESTON...OSCEOLA...CHARITON...ALBIA...OTTUMWA...BEDFORD... MOUNT AYR...LEON...CORYDON...CENTERVILLE...BLOOMFIELD 853 PM CST MON DEC 17 2012 ...WINTER STORM WATCH REMAINS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON... * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA ON WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW ON WEDNESDAY NIGHT BEFORE ENDING ON THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...5 TO 8 INCHES OF SNOW IS EXPECTED IN THE WATCH AREA. LOCAL AMOUNTS OF UP TO 10 INCHES WILL BE POSSIBLE WITH DRIFTS EVEN HIGHER. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG ON WEDNESDAY NIGHT FROM THE NORTH TO NORTHWEST. SUSTAINED WINDS OF 20 TO 30 MPH ARE EXPECTED WITH GUSTS OVER 35 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED AROUND DAYBREAK ON THURSDAY WITH BLIZZARD OR NEAR BLIZZARD CONDITIONS POSSIBLE WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND BLIZZARD OR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL...IN THIS CASE SNOW. CONTINUE TO MONITOR THE LATEST FORECASTS. IF FORECAST CONFIDENCE CONTINUES TO INCREASE...THIS WATCH MAY BE UPGRADED TO A BLIZZARD WATCH ON TUESDAY. && $$ SMALL
656 WWUS43 KDMX 180943 WSWDMX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DES MOINES IA 343 AM CST TUE DEC 18 2012 ...MAJOR WINTER STORM TO AFFECT CENTRAL IOWA WEDNESDAY AND THURSDAY... .A STRONG STORM WILL MOVE INTO THE OKLAHOMA PANHANDLE WEDNESDAY AFTERNOON BEFORE LIFTING NORTHEAST INTO NORTH CENTRAL ILLINOIS BY THURSDAY. RAIN AND SNOW IS EXPECTED TO OVERSPREAD IOWA WEDNESDAY BECOMING ALL SNOW WEDNESDAY NIGHT AND ENDING THURSDAY. VERY STRONG NORTHWEST WINDS WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING OF SNOW AND NEAR BLIZZARD CONDITIONS LATE WEDNESDAY NIGHT INTO THURSDAY RESULTING IN DANGEROUS TRAVEL OVER IOWA. IAZ025>028-033>039-044>050-057>062-070>075-081>086-092>097-181745- /O.CON.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN- GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE-BOONE-STORY-MARSHALL- TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR- MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE- WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS- INCLUDING THE CITIES OF...CLARION...HAMPTON...ALLISON...WAVERLY... SAC CITY...ROCKWELL CITY...FORT DODGE...WEBSTER CITY...ELDORA... GRUNDY CENTER...WATERLOO...DENISON...CARROLL...JEFFERSON... BOONE...AMES...MARSHALLTOWN...TOLEDO...AUDUBON...GUTHRIE CENTER... ADEL...DES MOINES...NEWTON...GRINNELL...ATLANTIC...GREENFIELD... WINTERSET...INDIANOLA...KNOXVILLE...OSKALOOSA...CORNING... CRESTON...OSCEOLA...CHARITON...ALBIA...OTTUMWA...BEDFORD... MOUNT AYR...LEON...CORYDON...CENTERVILLE...BLOOMFIELD 343 AM CST TUE DEC 18 2012 ...WINTER STORM WATCH REMAINS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON... * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW LATE WEDNESDAY EVENING BEFORE ENDING THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...5 TO 8 INCHES OF SNOW IS EXPECTED IN THE WATCH AREA. LOCAL AMOUNTS OF UP TO 10 INCHES WILL BE VERY POSSIBLE WITH DRIFTS EVEN HIGHER. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 33 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. BLIZZARD OR NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND BLIZZARD OR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL...IN THIS CASE SNOW. CONTINUE TO MONITOR THE LATEST FORECASTS. IF FORECAST CONFIDENCE REGARDING THE STRONG WINDS CONTINUES TO INCREASE...THIS WATCH MAY BE UPGRADED TO A BLIZZARD WATCH TODAY. && $$ REV
702 WWUS43 KDMX 181715 WSWDMX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DES MOINES IA 1115 AM CST TUE DEC 18 2012 ...MAJOR WINTER STORM TO AFFECT CENTRAL IOWA WEDNESDAY AND THURSDAY... .A STRONG STORM WILL MOVE INTO THE OKLAHOMA PANHANDLE WEDNESDAY AFTERNOON BEFORE LIFTING NORTHEAST INTO NORTH CENTRAL ILLINOIS BY THURSDAY. RAIN AND SNOW IS EXPECTED TO OVERSPREAD IOWA WEDNESDAY BECOMING ALL SNOW WEDNESDAY NIGHT AND ENDING THURSDAY. VERY STRONG NORTHWEST WINDS WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING OF SNOW AND NEAR BLIZZARD CONDITIONS LATE WEDNESDAY NIGHT INTO THURSDAY RESULTING IN DANGEROUS TRAVEL OVER IOWA. IAZ025>028-036>039-190115- /O.NEW.KDMX.WW.Y.0010.121218T1715Z-121218T2200Z/ /O.CON.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ WRIGHT-FRANKLIN-BUTLER-BREMER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK- INCLUDING THE CITIES OF...CLARION...HAMPTON...ALLISON...WAVERLY... WEBSTER CITY...ELDORA...GRUNDY CENTER...WATERLOO 1115 AM CST TUE DEC 18 2012 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 4 PM CST THIS AFTERNOON... ...WINTER STORM WATCH REMAINS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER WEATHER ADVISORY FOR SNOW AND LIGHT FREEZING RAIN...WHICH IS IN EFFECT UNTIL 4 PM CST THIS AFTERNOON. * TIMING OR SHORT TERM TRENDS...LIGHT TO LOCALLY MODERATE SNOW AND LIGHT FREEZING RAIN WILL PERSIST AT INTERVALS THROUGH THE MID- AFTERNOON HOURS. * STORM TOTAL SNOW/ICE ACCUMULATIONS...UP TO AN INCH OF ADDITIONAL SNOWFALL IS POSSIBLE NORTH TOWARD THE MINNESOTA BORDER. ANY ICE ACCUMULATIONS WILL BE VERY LIGHT. * IMPACTS...THE COMBINATION OF SNOW AND LIGHT ICE WILL MAKE FOR VERY SLICK AND HAZARDOUS DRIVING CONDITIONS AT TIMES. A WINTER STORM WATCH ALSO REMAINS IN EFFECT FOR THE AREA FROM WEDNESDAY AFTERNOON INTO THURSDAY. * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW LATE WEDNESDAY EVENING BEFORE ENDING THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...5 TO 8 INCHES OF SNOW IS EXPECTED IN THE WATCH AREA. LOCAL AMOUNTS OF UP TO 10 INCHES WILL BE VERY POSSIBLE WITH DRIFTS EVEN HIGHER. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 33 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. BLIZZARD OR NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND BLIZZARD OR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL...IN THIS CASE SNOW. CONTINUE TO MONITOR THE LATEST FORECASTS. IF FORECAST CONFIDENCE REGARDING THE STRONG WINDS CONTINUES TO INCREASE...THIS WATCH MAY BE UPGRADED TO A BLIZZARD WATCH TODAY. && $$ IAZ005>007-016-017-024-182200- /O.NEW.KDMX.WW.Y.0010.121218T1715Z-121218T2200Z/ KOSSUTH-WINNEBAGO-WORTH-HANCOCK-CERRO GORDO-HUMBOLDT- INCLUDING THE CITIES OF...ALGONA...FOREST CITY...NORTHWOOD... GARNER...MASON CITY...HUMBOLDT 1115 AM CST TUE DEC 18 2012 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 4 PM CST THIS AFTERNOON... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER WEATHER ADVISORY FOR ...WHICH IS IN EFFECT UNTIL 4 PM CST THIS AFTERNOON. * TIMING OR SHORT TERM TRENDS...LIGHT TO LOCALLY MODERATE SNOW AND LIGHT FREEZING RAIN WILL PERSIST AT INTERVALS THROUGH THE MID- AFTERNOON HOURS. * STORM TOTAL SNOW/ICE ACCUMULATIONS...UP TO AN INCH OF ADDITIONAL SNOWFALL IS POSSIBLE NORTH TOWARD THE MINNESOTA BORDER. ANY ICE ACCUMULATIONS WILL BE VERY LIGHT. * IMPACTS...THE COMBINATION OF SNOW AND LIGHT ICE WILL MAKE FOR VERY SLICK AND HAZARDOUS DRIVING CONDITIONS AT TIMES. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW...SLEET...OR FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITY...AND USE CAUTION WHILE DRIVING. && $$ IAZ033>035-044>050-057>062-070>075-081>086-092>097-190115- /O.CON.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ SAC-CALHOUN-WEBSTER-CRAWFORD-CARROLL-GREENE-BOONE-STORY-MARSHALL- TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR- MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE- WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS- INCLUDING THE CITIES OF...SAC CITY...ROCKWELL CITY...FORT DODGE... DENISON...CARROLL...JEFFERSON...BOONE...AMES...MARSHALLTOWN... TOLEDO...AUDUBON...GUTHRIE CENTER...ADEL...DES MOINES...NEWTON... GRINNELL...ATLANTIC...GREENFIELD...WINTERSET...INDIANOLA... KNOXVILLE...OSKALOOSA...CORNING...CRESTON...OSCEOLA...CHARITON... ALBIA...OTTUMWA...BEDFORD...MOUNT AYR...LEON...CORYDON... CENTERVILLE...BLOOMFIELD 1115 AM CST TUE DEC 18 2012 ...WINTER STORM WATCH REMAINS IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON... * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW LATE WEDNESDAY EVENING BEFORE ENDING THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...5 TO 8 INCHES OF SNOW IS EXPECTED IN THE WATCH AREA. LOCAL AMOUNTS OF UP TO 10 INCHES WILL BE VERY POSSIBLE WITH DRIFTS EVEN HIGHER. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 33 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. BLIZZARD OR NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND BLIZZARD OR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL...IN THIS CASE SNOW. CONTINUE TO MONITOR THE LATEST FORECASTS. IF FORECAST CONFIDENCE REGARDING THE STRONG WINDS CONTINUES TO INCREASE...THIS WATCH MAY BE UPGRADED TO A BLIZZARD WATCH TODAY. && $$ LEE
528 WWUS43 KDMX 182124 WSWDMX URGENT - WINTER WEATHER MESSAGE NATIONAL WEATHER SERVICE DES MOINES IA 324 PM CST TUE DEC 18 2012 ...DANGEROUS WINTER STORM TO AFFECT CENTRAL IOWA LATE WEDNESDAY INTO THURSDAY... .A STRONG STORM WILL MOVE INTO THE OKLAHOMA PANHANDLE WEDNESDAY AFTERNOON BEFORE LIFTING NORTHEAST INTO NORTH CENTRAL ILLINOIS BY THURSDAY MORNING. RAIN AND SNOW IS EXPECTED TO OVERSPREAD IOWA WEDNESDAY AFTERNOON BECOMING ALL SNOW WEDNESDAY NIGHT AND ENDING THURSDAY. VERY STRONG NORTHWEST WINDS WILL PRODUCE CONSIDERABLE BLOWING AND DRIFTING OF SNOW AND NEAR BLIZZARD CONDITIONS LATE WEDNESDAY NIGHT INTO THURSDAY RESULTING IN DANGEROUS TRAVEL OVER IOWA. IAZ025>028-036>039-190500- /O.CAN.KDMX.WW.Y.0010.000000T0000Z-121218T2200Z/ /O.UPG.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ /O.NEW.KDMX.WS.W.0004.121220T0000Z-121221T0000Z/ WRIGHT-FRANKLIN-BUTLER-BREMER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK- INCLUDING THE CITIES OF...CLARION...HAMPTON...ALLISON...WAVERLY... WEBSTER CITY...ELDORA...GRUNDY CENTER...WATERLOO 324 PM CST TUE DEC 18 2012 ...WINTER STORM WARNING IN EFFECT FROM 6 PM WEDNESDAY TO 6 PM CST THURSDAY... ...WINTER WEATHER ADVISORY IS CANCELLED... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW...WHICH IS IN EFFECT FROM 6 PM WEDNESDAY TO 6 PM CST THURSDAY. THE WINTER WEATHER ADVISORY HAS BEEN CANCELLED. THE WINTER STORM WATCH IS NO LONGER IN EFFECT. * TIMING...SNOW WILL OVERSPREAD THE AREA LATE WEDNESDAY AFTERNOON INTO THE EVENING. THE SNOW MAY INITIALLY BEGIN AS A MIXTURE OF RAIN AND SNOW BUT WILL TRANSITION TO ALL SNOW QUICKLY. THE SNOW WILL PERSIST WEDNESDAY NIGHT...HEAVY AT TIMES...WITH THE SNOW TAPERING OF ON THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...STORM TOTAL SNOWFALL OF 7 TO 11 INCHES IS POSSIBLE WITH LOCALLY HEAVIER AMOUNTS. SNOW DRIFTS SEVERAL FEET HIGH WILL BE POSSIBLE DUE TO THE VERY STRONG WINDS. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 30 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND NEAR BLIZZARD CONDITIONS. THIS WARNING MAY NEED TO BE UPGRADED TO A BLIZZARD WARNING SHOULD FORECAST CONDITIONS WARRANT. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY. && $$ IAZ005>007-016-017-024-190500- /O.CAN.KDMX.WW.Y.0010.000000T0000Z-121218T2200Z/ /O.NEW.KDMX.WS.A.0004.121220T0000Z-121221T0000Z/ KOSSUTH-WINNEBAGO-WORTH-HANCOCK-CERRO GORDO-HUMBOLDT- INCLUDING THE CITIES OF...ALGONA...FOREST CITY...NORTHWOOD... GARNER...MASON CITY...HUMBOLDT 324 PM CST TUE DEC 18 2012 ...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON... ...WINTER WEATHER ADVISORY IS CANCELLED... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON. THE WINTER WEATHER ADVISORY HAS BEEN CANCELLED. * TIMING...SNOW IS EXPECTED TO OVERSPREAD THE AREA ON LATE WEDNESDAY AFTERNOON AND PERSIST WEDNESDAY NIGHT BEFORE ENDING. * STORM TOTAL SNOW/ICE ACCUMULATIONS...2 TO 5 INCHES OF SNOW WITH LOCALLY HEAVIER AMOUNTS WILL BE POSSIBLE. * WINDS/VISIBILITY...WINDS WILL INCREASE FROM THE NORTH NORTHWEST ON WEDNESDAY NIGHT AT 20 TO 30 MPH WITH HIGHER GUSTS. NEAR BLIZZARD CONDITIONS WILL BE POSSIBLE LATE WEDNESDAY NIGHT INTO THURSDAY WITH CONSIDERABLE BLOWING SNOW. * IMPACTS...HAZARDOUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL. CONTINUE TO MONITOR THE LATEST FORECASTS. && $$ IAZ033>035-044>047-057>059-070>072-081-082-092-093-190500- /O.UPG.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ /O.NEW.KDMX.WS.W.0004.121219T2200Z-121220T1800Z/ SAC-CALHOUN-WEBSTER-CRAWFORD-CARROLL-GREENE-BOONE-AUDUBON-GUTHRIE- DALLAS-CASS-ADAIR-MADISON-ADAMS-UNION-TAYLOR-RINGGOLD- INCLUDING THE CITIES OF...SAC CITY...ROCKWELL CITY...FORT DODGE... DENISON...CARROLL...JEFFERSON...BOONE...AUDUBON... GUTHRIE CENTER...ADEL...ATLANTIC...GREENFIELD...WINTERSET... CORNING...CRESTON...BEDFORD...MOUNT AYR 324 PM CST TUE DEC 18 2012 ...WINTER STORM WARNING IN EFFECT FROM 4 PM WEDNESDAY TO NOON CST THURSDAY... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW...WHICH IS IN EFFECT FROM 4 PM WEDNESDAY TO NOON CST THURSDAY. THE WINTER STORM WATCH IS NO LONGER IN EFFECT. * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA LATE WEDNESDAY AFTERNOON. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC THROUGH JEFFERSON LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF A BEDFORD TO OSCEOLA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW LATE WEDNESDAY EVENING BEFORE ENDING ON THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...6 TO 10 INCHES OF SNOW IS EXPECTED BY THURSDAY MORNING. THE HEAVIEST SNOW AXIS WILL BE ALONG A LINE FROM ATLANTIC TO ADEL. THE LOWEST AMOUNTS ARE EXPECTED NEAR THE MISSOURI BORDER. SNOW DRIFTS SEVERAL FEET DEEP WILL BE POSSIBLE GIVEN THE STRONG WINDS. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 35 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND NEAR BLIZZARD CONDITIONS. THIS WARNING MAY NEED TO BE UPGRADED TO A BLIZZARD WARNING SHOULD FORECAST CONDITIONS WARRANT. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT... FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY. && $$ IAZ048>050-060>062-073>075-083>086-094>097-190500- /O.UPG.KDMX.WS.A.0003.121219T1800Z-121221T0000Z/ /O.NEW.KDMX.WS.W.0004.121220T0000Z-121221T0000Z/ STORY-MARSHALL-TAMA-POLK-JASPER-POWESHIEK-WARREN-MARION-MAHASKA- CLARKE-LUCAS-MONROE-WAPELLO-DECATUR-WAYNE-APPANOOSE-DAVIS- INCLUDING THE CITIES OF...AMES...MARSHALLTOWN...TOLEDO... DES MOINES...NEWTON...GRINNELL...INDIANOLA...KNOXVILLE... OSKALOOSA...OSCEOLA...CHARITON...ALBIA...OTTUMWA...LEON... CORYDON...CENTERVILLE...BLOOMFIELD 324 PM CST TUE DEC 18 2012 ...WINTER STORM WARNING IN EFFECT FROM 6 PM WEDNESDAY TO 6 PM CST THURSDAY... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW...WHICH IS IN EFFECT FROM 6 PM WEDNESDAY TO 6 PM CST THURSDAY. THE WINTER STORM WATCH IS NO LONGER IN EFFECT. * TIMING...PRECIPITATION WILL OVERSPREAD CENTRAL IOWA BY EARLY WEDNESDAY EVENING. SNOW IS EXPECTED ALONG AND NORTH OF A BOONE TO WATERLOO LINE. RAIN IS EXPECTED IN SOUTHERN IOWA SOUTH OF AN OSCEOLA TO OSKALOOSA LINE. IN BETWEEN...A RAIN AND SNOW MIX IS EXPECTED. THIS PRECIPITATION WILL CHANGE TO ALL SNOW LATE WEDNESDAY EVENING BEFORE ENDING ON THURSDAY MORNING. * STORM TOTAL SNOW ACCUMULATION...6 TO 12 INCHES OF SNOW IS EXPECTED BY THURSDAY MORNING. THE HEAVIEST SNOW AXIS WILL BE ALONG A LINE FROM DES MOINES TO TAMA. THE LOWEST AMOUNTS ARE EXPECTED NEAR THE MISSOURI BORDER. SNOW DRIFTS SEVERAL FEET DEEP WILL BE POSSIBLE GIVEN THE STRONG WINDS. * WINDS/VISIBILITY...WINDS WILL BECOME VERY STRONG WEDNESDAY NIGHT FROM THE NORTH NORTHWEST. SUSTAINED WINDS OF 25 TO 35 MPH ARE EXPECTED WITH GUSTS OVER 45 MPH POSSIBLE. THE STRONGEST WINDS ARE EXPECTED A FEW HOURS PRIOR TO DAYBREAK THROUGH NOON THURSDAY. NEAR BLIZZARD CONDITIONS MAY OCCUR WITH VISIBILITIES REDUCED BELOW ONE QUARTER OF A MILE FROM TIME TO TIME. * IMPACTS...VERY DANGEROUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR VERY DIFFICULT TRAVEL AND NEAR BLIZZARD CONDITIONS. THIS WARNING MAY NEED TO BE UPGRADED TO A BLIZZARD WARNING SHOULD FORECAST CONDITIONS WARRANT. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY. && $$ IAZ004-015-023-190500- /O.NEW.KDMX.WS.A.0004.121220T0000Z-121221T0000Z/ EMMET-PALO ALTO-POCAHONTAS- INCLUDING THE CITIES OF...ESTHERVILLE...EMMETSBURG...POCAHONTAS 324 PM CST TUE DEC 18 2012 ...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON... THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON. * TIMING...SNOW IS EXPECTED TO OVERSPREAD THE AREA ON LATE WEDNESDAY AFTERNOON AND PERSIST WEDNESDAY NIGHT BEFORE ENDING. * STORM TOTAL SNOW/ICE ACCUMULATIONS...2 TO 5 INCHES OF SNOW WITH LOCALLY HEAVIER AMOUNTS WILL BE POSSIBLE. * WINDS/VISIBILITY...WINDS WILL INCREASE FROM THE NORTH NORTHWEST ON WEDNESDAY NIGHT AT 20 TO 30 MPH WITH HIGHER GUSTS. NEAR BLIZZARD CONDITIONS WILL BE POSSIBLE LATE WEDNESDAY NIGHT INTO THURSDAY WITH CONSIDERABLE BLOWING SNOW. * IMPACTS...HAZARDOUS CONDITIONS ARE EXPECTED TO DEVELOP ON WEDNESDAY NIGHT INTO THURSDAY MORNING. BE PREPARED FOR NEAR BLIZZARD CONDITIONS. PRECAUTIONARY/PREPAREDNESS ACTIONS... A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL. CONTINUE TO MONITOR THE LATEST FORECASTS. && $$ CC
What forecasters said that day
The local office's own words before this winter storm watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Des Moines, IA wrote its last area forecast discussion before this winter storm watch went out at Dec 17, 4:00 PM CST, 1 minute earlier.
Area forecast discussion, Dec 17, 4:00 PM CST, 1 minute before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 400 PM CST MON DEC 17 2012 ...SIGNIFICANT WINTER STORM TO IMPACT THE MIDWEST AND PLAINS WEDNESDAY AND THURSDAY... .SHORT TERM /TONIGHT/... LOW PRESSURE OVER NORTHEAST WYOMING WILL SHIFT EAST ACROSS SOUTH DAKOTA AND NEBRASKA AND REACH NORTHWEST IOWA LATE TONIGHT. AN ASSOCIATED UPPER LEVEL SHORT WILL SPREAD INCREASING QG FORCING ACROSS CENTRAL IOWA. IN ADDITION...STRONG THETA-E ADVECTION WILL ARRIVE AFTER MIDNIGHT THROUGH CENTRAL AND NORTHWEST IOWA. THE BEST COMBINATION OF FORCING IS OVER CENTRAL IA NEAR DES MOINES AND AMES BETWEEN 3 AM TO 6 AM HOWEVER THE DEEPER MOISTURE WILL BE FARTHER NORTH. TYPICALLY THIS TIME OF YEAR FORCING TRUMPS DEEP MOISTURE THEREFORE CERTAINLY SHOULD HAVE PRECIPITATION FARTHER SOUTH THAN WHAT MOST MODEL GUIDANCE PRECIPITATION FIELDS WOULD SUGGEST. WARM ADVECTION IN THE LOW LEVELS IS EXPECTED AS WELL OVERNIGHT RESULTING IN NON-DIURNAL TEMPERATURES. THIS COULD SWITCH PRECIPITATION TYPE TO RAIN ON THE SOUTHERN FRINGES. NOT CONFIDENT IN POTENTIAL OF FREEZING RAIN WITH UNCERTAINTY IN ARRIVAL OF WARMER AIR ALOFT...THOUGH CAN NOT TOTALLY DISCOUNT. POTENTIAL AS WELL FOR POCKETS OF LOWER VISIBILITIES DUE TO FOG THOUGH LOW LEVEL WARM ADVECTION SHOULD LIMIT AREAL COVERAGE OF VISIBILITIES BELOW 2SM. .LONG TERM /TUESDAY THROUGH MONDAY/... WILL SEE SOME LINGERING POPS IN THE NORTH ON TUESDAY MORNING AS THE SYSTEM GRADUALLY DEPARTS TO THE EAST. SOME LIGHT ACCUMULATIONS WILL STILL BE POSSIBLE AROUND MASON CITY BEFORE MIDDAY BUT PCPN IS EXPECTED TO END BY MIDDAY. THE WEATHER WILL BE TRANQUIL FROM TUESDAY AFTERNOON INTO EARLY WEDNESDAY MORNING BEFORE MAJOR SYSTEM BEGINS TO AFFECT THE FORECAST AREA. THIS MAJOR STORM IS CURRENTLY OFF THE WEST COAST AND WILL COME ASHORE LATE TONIGHT INTO TUESDAY. THEREFORE...THERE IS LITTLE RESOLUTION OF THE SYSTEM BY THE UPPER AIR NETWORK WHICH IS LIKELY CAUSING SOME OF THE DIFFERENCES SEEN IN THE MODEL RUNS. INITIALLY ON WEDNESDAY...RIDGE AXIS WILL BE IN PLACE ACROSS THE NORTHEAST WITH RELATIVELY QUITE WEATHER. HOWEVER...BY MIDDAY...FORCING WILL RAPIDLY INCREASE AS ISENTROPIC LIFT BEGINS IN EARNEST. STRONG FRONTOGENETICAL FORCING ALSO ARRIVES ACROSS CENTRAL INTO NORTHERN IOWA BY LATE AFTERNOON WHICH WILL LIKELY ENHANCE PCPN RATES IN THOSE LOCATIONS. PCPN WILL BREAK OUT DURING THE AFTERNOON AND INCREASE IN BOTH COVERAGE AND INTENSITY AS THE AFTERNOON PROGRESSES. SNOW IS EXPECTED ALONG AND NORTH OF AN ATLANTIC TO WATERLOO LINE WITH A BAND OF MIXED PCPN OF 50 MILES WIDE OR SO SOUTH OF THE SNOW. RAIN IS EXPECTED ALONG THE MISSOURI BORDER AS READINGS REMAIN ABOVE FREEZING. CONDITIONS DETERIORATE RAPIDLY ON WEDNESDAY NIGHT AS COLD ADVECTION INTENSIFIES ACROSS THE STATE. UPPER SYSTEM WILL EJECT FROM SOUTHERN PLAINS AND RACE NORTHEAST TO NEAR QUINCY ILLINOIS BY DAYBREAK. SYSTEM WILL BE DEEPENING AND BECOMING NEGATIVELY TILTED WITH TIME AS SURFACE LOW STRENGTHENS. PCPN ACRS THE FORECAST AREA WILL BECOME ALL SNOW BY MIDNIGHT AS COLD AIR IS DRAWN SOUTHWARD. WINDS ARE LIKELY TO BECOME A VERY SERIOUS ISSUE AFTER MIDNIGHT AND CERTAINLY BY DAYBREAK ON THURSDAY. 925MB WINDS WILL BE NEAR OR EVEN SLIGHTLY ABOVE 50KTS WITH MOS OUTPUT SHOWING SUSTAINED WINDS OF 30KTS IN MANY LOCATIONS IN CENTRAL IOWA. THIS EVENT MAY BECOME MORE OF A BLIZZARD INTO THURSDAY MORNING AS THE WINDS INCREASE AND WILL HAVE TO BE MONITORED CLOSELY. SNOW ON WEDNESDAY NIGHT WILL BE HEAVIEST IN THE EVENING AS MID LEVEL FORCING IS MAXIMIZED. SOME CONVECTIVE SNOW WILL BE POSSIBLE AS WELL WITH NEGATIVE EPV ACROSS MUCH OF THE STATE WITH DECENT MID LEVEL LAPSE RATES. CONDITIONS WILL BE POOR ON THURSDAY MORNING WITH VERY STRONG WINDS DESPITE THE SNOWFALL ENDING. GIVEN ALL OF THIS...HAVE ISSUED A WINTER STORM WATCH FOR MUCH OF CENTRAL IOWA FROM MIDDAY WEDNESDAY INTO THURSDAY FOR THE POTENTIAL OF HEAVY SNOWFALL AND VERY STRONG WINDS. AN UPGRADE TO BLIZZARD WATCH MAY BE NEEDED SHOULD FORECAST WINDS REMAIN STRONG OR INCREASE. THE WEATHER BEYOND THURSDAY IS RELATIVELY QUIET WITH LITTLE CHANGE IN THE FORECAST. MAIN CONCERN IS THAT TEMPERATURES WOULD BE TOO WARM GIVEN THE FRESH SNOW COVER ACROSS THE AREA. && .AVIATION...17/18Z LOW STRATUS WILL PREVAIL THROUGH MUCH OF THE PERIOD. POSSIBLE BRIEF BREAKS THIS AFTERNOON HOWEVER STRATUS DECK DROPPING THROUGH WRN MN AND EASTERN SD AND EASTERN NEBRASKA WILL ROTATE INTO CNTRL IA LATER THIS AFTERNOON AND TONIGHT. MVFR FOG POSSIBLE THROUGH THE REMAINDER OF THE DAY ESPECIALLY NEAR THE IFR STRATUS. POSSIBLE IT COULD GO MUCH LOWER TONIGHT HOWEVER AT THIS TIME THE FOCUS IS ON CIGS. A BOUNDARY WILL MOVE THROUGH TUE MORNING WITH A SWITCH TO BREEZY WESTERLY WINDS AND GRADUALLY IMPROVING CONDITIONS. && .DMX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY AFTERNOON FOR ADAIR-ADAMS-APPANOOSE-AUDUBON-BLACK HAWK-BOONE- BREMER-BUTLER-CALHOUN-CARROLL-CASS-CLARKE-CRAWFORD-DALLAS-DAVIS- DECATUR-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-HARDIN-JASPER-LUCAS- MADISON-MAHASKA-MARION-MARSHALL-MONROE-POLK-POWESHIEK-RINGGOLD- SAC-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-WAYNE-WEBSTER-WRIGHT. && SHORT TERM...DONAVON LONG TERM...COGIL AVIATION...DONAVON
Hazardous weather outlook, Dec 17, 4:01 PM CST, 0 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 401 PM CST MON DEC 17 2012 IAZ025>028-033>039-044>050-057>062-070>075-081>086-092>097-182215- WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN-WEBSTER-HAMILTON-HARDIN- GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE-BOONE-STORY-MARSHALL-TAMA- AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR-MADISON- WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR- RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS- 401 PM CST MON DEC 17 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND SOUTH CENTRAL IOWA. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A WINTER STORM WATCH IS IN EFFECT FOR THE AREA. PLEASE REFER TO THE NATIONAL WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR FURTHER DETAILS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED HOWEVER SNOWFALL AND BLOWING SNOW REPORTS WOULD BE APPRECIATED WEDNESDAY AFTERNOON THROUGH THURSDAY. IAZ004>007-015>017-023-024-182215- EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- POCAHONTAS-HUMBOLDT- 401 PM CST MON DEC 17 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL IOWA. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY LIGHT TO MODERATE ACCUMULATIONS OF SNOWFALL ARE POSSIBLE WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT. IN ADDITION...STRONG NORTHWEST WINDS WILL DEVELOP WEDNESDAY NIGHT AND CREATE THE POTENTIAL FOR BLOWING AND DRIFTING OF SNOW THROUGH THURSDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED HOWEVER SNOWFALL AND BLOWING SNOW REPORTS WOULD BE APPRECIATED WEDNESDAY AFTERNOON THROUGH THURSDAY.
Nearby
Winter Storm Watches in Iowa, 2012Every winter storm watch in 2012
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.