National Weather Service National Headquarters

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

000
FXUS63 KDVN 280536
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1136 PM CST FRI FEB 27 2015

.UPDATE...
ISSUED AT 1125 PM CST FRI FEB 27 2015

TEMPERATURES CONTINUE TO FALL UNDER NEARLY IDEAL RADIATIONAL
COOLING CONDITIONS. MLI...NOW AT -13 HAS AT LEAST MATCHED THE
RECORD SET THIS MORNING. IT IS LIKELY THAT MLI AND THE CLIMATE
SITES LISTED IN THE CLIMATE SECTION WILL ESTABLISH NEW RECORDS FOR
THE 28TH AS WELL.

&&

.SYNOPSIS...
ISSUED AT 304 PM CST FRI FEB 27 2015

12Z UA ANALYSIS HAS A LARGE 850MB ARCTIC HIGH OVER THE PLAINS WITH
THE 850MB ARCTIC FRONT NEAR THE GULF COAST. SATELLITE TRENDS THROUGH
MID AFTERNOON SHOW CLEAR SKIES ACROSS MUCH OF THE MIDWEST WITH LOW
CLOUDS IN THE CENTRAL AND SOUTHERN PLAINS.

18Z SFC ANALYSIS HAS THE ARCTIC HIGH WEST OF THE MISSISSIPPI WITH A
SUBTLE WEAK TROF IN THE NORTHERN PLAINS. DEW POINTS WERE BELOW ZERO
ACROSS THE UPPER MIDWEST AND WESTERN GREAT LAKES WITH TEENS AND
HIGHER FROM THE OHIO VALLEY INTO THE SOUTHERN PLAINS.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 304 PM CST FRI FEB 27 2015

ANOTHER QUIET AND VERY COLD NIGHT WILL BE SEEN ACROSS THE AREA WITH
TEMPERATURES 20 TO 30 DEGREES BELOW NORMAL. LOWS MAY COME CLOSE TO
RECORDS AGAIN BY SUNRISE SATURDAY. REFER TO THE CLIMATE SECTION
FOR SPECIFIC NUMBERS.

BASED ON EXPECTED LOWS AND LIGHT WINDS...ANOTHER WIND CHILL ADVISORY
WILL BE NEEDED LATE TONIGHT INTO SATURDAY MORNING. THE AREA IS
GENERALLY THE I-80 CORRIDOR TO THE MISSISSIPPI RIVER ON NORTH ALONG
WITH JO DAVIESS AND CARROLL COUNTIES IN ILLINOIS. CONDITIONS MAY BE
MARGINAL IN SOME AREAS IF WINDS REMAIN LIGHT.

DRY CONDITIONS WILL CONTINUE ACROSS THE AREA SATURDAY MORNING WITH
INCREASING CLOUDS THROUGH THE DAY. LIGHT SNOW SHOULD BEGIN
DEVELOPING/SPREADING INTO THE FAR SOUTHWEST AREAS AROUND MID
AFTERNOON AND VERY SLOWLY OVERSPREAD THE SOUTHWEST THIRD OF THE AREA
BY SUNSET. ANY SNOWFALL AMOUNTS SHOULD BE A TRACE TO A DUSTING AT
BEST.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 304 PM CST FRI FEB 27 2015

FORECAST FOCUS ON TWO STORM SYSTEMS TO DEAL WITH THROUGH EARLY NEXT
WEEK FOLLOWED BY MODERATING TEMPERATURES LATE NEXT WEEK.

SATURDAY NIGHT AND SUNDAY...LATEST MODEL TRENDS IS FOR SOMEWHAT OF A
SHIFT TO THE SOUTH WITH REGARD TO THE STORM SYSTEM THAT SHOULD BRING
ACCUMULATING SNOW. APPEARS A FRONTOGENETICAL BAND OF FORCING SETTING
UP ROUGHLY ACROSS OUR SOUTH HALF WITH WARM AIR ADVECTION DURING THIS
TIME. THE FARTHER NORTH YOU GO THE LESS SNOW. THE BULK OF THE
ACCUMULATIONS SHOULD OCCUR LATE SATURDAY NIGHT AND SUNDAY MORNING.
AS OF THIS FORECAST AMOUNTS SHOULD RANGE FROM LESS THAN AN INCH
ALONG HIGHWAY 20 TO AROUND 2 INCHES IN THE QUAD CITIES TO 2 TO 4
INCHES IN OUR SOUTHERN COUNTIES. HEADLINES MAY NEED TO BE ISSUED IN
THE NEAR FUTURE FOR PORTIONS OF THE CWA. THESE AMOUNTS ARE NOT
ETCHED IN STONE YET AS MODELS COULD STILL SHIFT THE TRACK EITHER
NORTH OR SOUTH.

MONDAY NIGHT AND TUESDAY...SIGNIFICANT STORM SYSTEM STILL EVIDENT ON
MODELS SO CONFIDENCE MODERATE TO HIGH ON THAT. HOWEVER...CONFIDENCE
IS LOW ON THE TIMING/DURATION OF PRECIPITATION TYPES. THE MODELS
SEEM TO BE SOMEWHAT COLDER IN OUR FAR NORTH AS THE 0C 850 LINE IS
VERY CLOSE TO HIGHWAY 20. AS OF NOW FREEZING RAIN/SLEET/SNOW WOULD
DEVELOP MONDAY NIGHT BUT THEN CHANGE TO PLAIN RAIN TUESDAY AS STRONG
WARM AIR ADVECTION IS DRIVEN BY A 60 KNOT LOW LEVEL JET. THE TRICKY
PART IS HOW LONG WE MAY HAVE ICE ACCUMULATIONS BEFORE TEMPERATURES
WARM ABOVE FREEZING. HAVE INTRODUCED ISOLATED THUNDER FOR TUESDAY IN
OUR SOUTHERN CWA WITH SUCH A STRONG LOW LEVEL JET/THETA-E ADVECTION.
THERE IS ALSO A NICE MOISTURE TRANSPORT OF DEEP GULF MOISTURE SO
THERE IS THE POTENTIAL FOR AT LEAST AN INCH OF RAINFALL. ONCE
AGAIN...HOW MUCH OF THIS IS ICE AND SNOW INITIALLY REMAINS TO BE
SEEN.

TUESDAY NIGHT...AS COLDER AIR ARRIVES BEHIND THE DEEPENING CYCLONE
THE RAIN SHOULD CHANGE TO SNOW BUT AMOUNTS IF ANY ARE DIFFICULT TO
DETERMINE AT THIS POINT.

WEDNESDAY THROUGH FRIDAY...DRY AND COLDER WEDNESDAY AND THURSDAY AS
WE GET INTO A NORTHWEST FLOW. HOWEVER...BY FRIDAY TEMPERATURES
MODERATE AS FLOW BECOMES MORE ZONAL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1135 PM CST FRI FEB 27 2015

CONDITIONS WILL REMAIN VFR AS HIGH PRESSURE PROVIDES MOSTLY CLEAR
SKIES...LIGHT WINDS AND BITTER COLD TEMPERATURES TONIGHT THROUGH SATURDAY
MORNING. A WINTER STORM SYSTEM APPROACHING FROM THE SOUTHWEST WILL
TURN LIGHT WINDS TO THE SOUTHEAST SATURDAY. IT WILL ALSO SPREAD
LIGHT SNOW INTO THE BRL SITE TOWARD EVENING...LIKELY REACHING AT
LEAST MLI AND CID BETWEEN 00Z AND 06Z. WITH A RATHER WEAK SYSTEM
BATTLING DRY AIR...THE ADVERTISED TRANSITION TO MVFR CONDITIONS
WITH LIGHT SNOW DURING THIS PERIOD IS LOW CONFIDENCE.

&&

.CLIMATE...
ISSUED AT 304 PM CST FRI FEB 27 2015

RECORD LOWS FOR FEBRUARY 28...

MOLINE.........-9 IN 1962
CEDAR RAPIDS...-17 IN 1962
DUBUQUE........-10 IN 1962
BURLINGTON.....-7 IN 1962

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WIND CHILL ADVISORY FROM 3 AM TO 9 AM CST SATURDAY FOR CEDAR-
     CLINTON-JACKSON-JOHNSON-JONES-MUSCATINE-SCOTT.

     WIND CHILL ADVISORY UNTIL 9 AM CST SATURDAY FOR BENTON-BUCHANAN-
     DELAWARE-DUBUQUE-IOWA-LINN.

IL...WIND CHILL ADVISORY FROM 3 AM TO 9 AM CST SATURDAY FOR CARROLL-
     JO DAVIESS-ROCK ISLAND.

MO...NONE.
&&

$$

UPDATE...SHEETS
SYNOPSIS...08
SHORT TERM...08
LONG TERM...HAASE
AVIATION...SHEETS
CLIMATE...08