000 AWUS83 KDMX 222231 RWSDMX IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-230400- WEATHER SUMMARY FOR IOWA NATIONAL WEATHER SERVICE DES MOINES IA 500 PM CST WED DEC 22 2004 ARCTIC AIR AND SUNSHINE CONTINUED OVER MUCH OF THE STATE LATE THIS WEDNESDAY AFTERNOON. TEMPERATURES CONTINUED VERY COLD ACROSS IOWA WITH READINGS RANGING FROM 4 DEGREES ABOVE ZERO AT MASON CITY TO 19 DEGREES AT SHENANDOAH. THE WIND WAS GENERALLY FROM THE NORTHWEST AT 8 TO 13 MPH STATEWIDE. HIGH CLOUDS HAD INCREASED OVER THE SOUTHEASTERN PORTION OF THE STATE WITH SOME MID-LEVEL CLOUDS EVIDENT OVER THE FAR NORTHEASTERN COUNTIES OF IOWA BY 3 PM. FARTHER NORTH IN MINNESOTA AFTERNOON TEMPERATURES STRUGGLED TO GET ABOVE ZERO. BY MID-AFTERNOON INTERNATIONAL FALLS WAS STILL REPORTING A TEMPERATURE OF 9 BELOW ZERO WITH MINNEAPOLIS AT 2 ABOVE ZERO. AN AREA OF ARCTIC HIGH PRESSURE RESPONSIBLE FOR THE COLD AIR WILL HOLD STRONG OVER THE EASTERN DAKOTAS TONIGHT AND EARLY THURSDAY. THE HIGH IS EXPECTED TO AFFECT IOWA THROUGH FRIDAY WITH SOME MODERATION IN TEMPERATURE AS CHRISTMAS EVE APPROACHES. A DEVELOPING AREA OF LOW PRESSURE OVER THE SOUTHERN MISSISSIPPI RIVER VALLEY WILL LIFT NORTHEAST THROUGH THE OHIO RIVER VALLEY TONIGHT AND THURSDAY. THIS SYSTEM WILL SPREAD SIGNIFICANT SNOW TO PORTIONS OF THESE AREAS...WITH AMOUNTS EXCEEDING A FOOT POSSIBLE. IOWA WILL BE SANDWICHED BETWEEN THE STORM TO THE SOUTHEAST AND THE LARGE HIGH TO THE WEST. THIS WILL PROVIDE CONTINUED REINFORCEMENT OF THE ARCTIC AIR ON NORTH TO NORTHWEST WINDS. WITH THE WIND INCREASING IN STRENGTH LATE TONIGHT AND THURSDAY MORNING AND COLD AIR CONTINUING TO FUNNEL SOUTH...WIND CHILL ADVISORIES WILL BE IN EFFECT FOR THE NORTHERN HALF OF IOWA ALONG WITH PORTIONS OF MINNESOTA... WISCONSIN...AND ILLINOIS LATE TONIGHT AND THURSDAY. LOW TEMPERATURES TONIGHT WILL FALL BELOW ZERO OVER MUCH OF THE STATE WITH READINGS RANGING FROM NEAR ZERO IN THE SOUTH TO NEAR 10 BELOW OVER THE NORTH. HIGHS ON THURSDAY WILL RECOVER TO NEAR ZERO NORTH AND TO NEAR 10 ABOVE ZERO SOUTH. LOWS FRIDAY MORNING SHOULD FALL AROUND TO NEAR 5 BELOW SOUTH TO 12 BELOW NORTH MAKING FRIDAY MORNING THE COLDEST MORNING SO FAR THIS SEASON. WIND CHILLS WILL BE EVEN COLDER...WITH VALUES APPROACHING 15 TO 30 BELOW LATE TONIGHT THROUGH NOON WEDNESDAY AND POSSIBLY AGAIN THURSDAY NIGHT. $$ VACHALEK