000
FXUS63 KDVN 260955
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
355 AM CST THU FEB 26 2015

.SYNOPSIS...
ISSUED AT 324 AM CST THU FEB 26 2015

LIGHT SNOW OVER PORTIONS OF FAR EASTERN IOWA AND NORTHERN ILLINOIS
CONTINUED TO DECREASE IN INTENSITY DURING THE EARLY MORNING HOURS.
AT 3 AM CST...A HIGHER INTENSITY SNOW BAND WAS LOCATED FROM
MACOMB...TO GALESBURG AND CANTON. EARLY MORNING TEMPERATURES RANGED
FROM THE SINGLE DIGITS IN CENTRAL AND NORTHEAST IOWA...TO THE TEENS
ALONG AND SOUTH OF INTERSTATE 80. A NORTH BREEZE WAS PRODUCING
SUB-ZERO WIND CHILLS IN MANY LOCATIONS...WITH THE COLDEST VALUES
NORTH OF U.S. HIGHWAY 20.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 324 AM CST THU FEB 26 2015

WITH LIGHT SNOW DIMINISHING ACROSS THE SOUTHEAST HALF OF THE
FORECAST AREA EARLY THIS MORNING...THE FOCUS OF THE SHORT TERM
PERIOD TURNS TO THE BITTERLY COLD TEMPERATURES AND WIND CHILLS.

LIGHT SNOW WILL LIKELY PERSIST THROUGH MID-MORNING IN THE
SOUTHEAST...WITH AN ADDITIONAL LIGHT DUSTING POSSIBLE. STRONG CAA
WILL CONTINUE THROUGH THE DAY WITH AFTERNOON TEMPS ONLY REBOUNDING
INTO THE SINGLE DIGITS NORTHWEST TO MID TEENS FAR SOUTH. FOR
TONIGHT...HIGH PRESSURE WILL NOSE IN FROM THE WEST...AND WILL THE
FRESH SNOW COVER...HAVE CONTINUED THE TREND OF UNDERCUTTING
GUIDANCE. KEPT LOWS SIMILAR TO PREVIOUS FORECAST...GENERALLY IN THE
9 TO 16 BELOW ZERO RANGE. IF THIS VERIFIES...BURLINGTON AND CEDAR
RAPIDS WILL HAVE NEW RECORD LOWS FOR THE 27TH...DUBUQUE AND MOLINE
WOULD BE CLOSE TO THEIR RECORDS OF 12 BELOW ZERO. ALTHOUGH THE
NORTHWEST WIND WILL BE RELATIVELY LIGHT...NOT EXPECTING CALM
CONDITIONS...THUS WIND CHILLS OF 20 TO 30 BELOW ZERO ARE A GOOD BET
OVER MOST OF THE FORECAST AREA WITH THE POSSIBLE EXCEPTION OF THE
FAR SOUTH. A WIND CHILL ADVISORY WILL BE CONSIDERED BY THE DAY CREW.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 324 AM CST THU FEB 26 2015

FRIDAY...VERY COLD PERIOD AS ARCTIC ~1043 MB HIGH BUILDS INTO THE
MIDWEST. MAX TEMPS ARE FORECAST TO BE IN THE UPPER SINGLE DIGITS TO
MID TEENS. FRESH POWDERY SNOW ON THE GROUND/LIGHT WINDS (POSSIBLY
DECOUPLED AT TIMES)/AND MAINLY CLEAR SKIES WILL SET THE STAGE FOR
VERY COLD OVERNIGHT LOWS. SUPERBLEND HAS TRENDED COLDER AS EXPECTED
GIVEN ATMOSPHERIC SETUP.

ANTICIPATE WIDESPREAD LOWS BETWEEN +/- 3 DEGREES OF -10 F WHICH
WOULD BE NEAR RECORD TERRITORY FOR LATE FEBRUARY...SLIGHTLY WARMER
TEMPS ARE LIKELY SOUTH OF BURLINGTON. WINDS WILL VARY BETWEEN CALM
AND 6 KTS BUT WILL OCCASIONALLY BE ENOUGH TO CREATE DANGEROUS WIND
CHILLS BETWEEN -20 TO -30 F. VALUES NEAR -30 F SHOULD BE ISOLATED
AND SHORT-LIVED.

SATURDAY AND SUNDAY...SIGNIFICANT PATTERN CHANGE WILL OCCUR DURING
THIS TIME AS 130+ KT UPPER JET DIGS OUT A LARGE TROUGH OVER THE
WESTERN U.S...CAUSING A BIG SHIFT IN THE ORIENTATION OF THE 850 MB
BAROCLINIC ZONE TO A SW-NE DIRECTION.

THERE HAS BEEN A CONSISTENT SIGNAL OF SIGNIFICANT LOW/MID-LEVEL
MOISTURE ADVECTION FROM THE SW U.S. AND FROM THE GULF OF MEXICO (PER
850-500 MB RH PLOTS) FOR SAT NIGHT INTO SUN. POSITIVE PRESSURE
ADVECTION/ISENTROPIC LIFT WILL BRING A PERIOD OF ACCUMULATING SNOW
TO E IOWA/W ILLINOIS/NE MISSOURI DURING THIS TIME. PRELIMINARY
AMOUNTS OF 2-4 INCHES ARE POSSIBLE BY EARLY SUN MORNING. ADDITIONAL
ACCUMULATIONS ARE LIKELY AFTER THIS TIME.

WITH THE LACK OF A STRONG SHORTWAVE TROUGH/VORTICITY MAX...MODELS
DEVELOP LINEAR-LOOKING FRONTAL PRECIP ON SUN AND DO NOT DEVELOP A
COHERENT SFC LOW. THIS SHOULD ACT TO DECREASE THE AREAL COVERAGE OF
THE PRECIP THROUGH THE DAY. RIGHT NOW AREAS TO THE SOUTH OF THE QUAD
CITIES STAND THE BEST CHANCE TO RECEIVE THE HIGHEST SNOW TOTALS.
DAYTIME TEMPS WILL BE IN THE UPPER TEENS TO LOWER 20S ON SAT AND THE
UPPER 20S TO LOWER 30S ON SUN.

MONDAY AND TUESDAY...CHANCE OF PRECIP MORE LIKELY LATER IN THE DAY
AND INTO TUE. MODELS STILL LACK CONSISTENCY REGARDING DEVELOPMENT OF
AN ORGANIZED SFC LOW THAT MAY TRACK THROUGH WESTERN GREAT LAKES AS
500 MB VORTICITY MAX PROPAGATES OUT OF THE FOUR CORNERS AREA. THE
00Z/2.26 ECMWF HAS A WELL ORGANIZED SFC LOW TRACKING FROM KANSAS TO
NORTHERN INDIANA WHICH IS FAVORABLE FOR WIDESPREAD PRECIP IN THE DVN
CWA. THE GFS IS MUCH LESS ORGANIZED WITH THE LOW.

WARMER AIR ALOFT MAY MAKE IT FAR ENOUGH NORTH TO BRING VARYING
PRECIP TYPES TO PORTIONS OF THE FORECAST AREA. STAY TUNED. EARLY
LOOK AT FORECAST HIGHS ARE IN THE LOWER TO UPPER 30S ON TUE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1139 PM CST WED FEB 25 2015

OUTSIDE A FEW FLURRIES...SNOW HAS ENDED AT CID AND DBQ AND VFR
CONDITIONS ARE EXPECTED TO PREVAIL THERE THROUGH THE ENTIRE TAF
CYCLE. AT MLI AND BRL...MVFR AND PERIODS OF IFR ARE EXPECTED
OVERNIGHT AS THE BACK EDGE OF SNOW WITH A DEPARTING WINTER STORM
SYSTEM RETREATS TO THE SOUTHEAST. FORECAST MODELS APPEAR TO BE TOO
AGGRESSIVE WITH LOW CLOUDS AND MVFR CIGS OVER MUCH OF EASTERN IA INTO
THURSDAY MORNING...AND HAVE INSTEAD KEPT CONDITIONS VFR. A COLD
HIGH PRESSURE SYSTEM MOVING IN FROM THE NORTHERN PLAINS THURSDAY
WILL RESULT IN DIMINISHING NW WINDS AND MOSTLY CLEAR SKIES BY
THURSDAY NIGHT.

&&

.CLIMATE...
ISSUED AT 324 AM CST THU FEB 26 2015

RECORD LOWS FOR FEBRUARY 27...

MOLINE.........-12 IN 1934
CEDAR RAPIDS...-10 IN 1897
DUBUQUE........-12 IN 1879
BURLINGTON.....-7 IN 1934

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR HANCOCK-
     HENDERSON-MCDONOUGH-WARREN.

MO...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR CLARK-
     SCOTLAND.

&&

$$

SYNOPSIS...RP KINNEY
SHORT TERM...RP KINNEY
LONG TERM...UTTECH
AVIATION...SHEETS
CLIMATE...RP KINNEY