000
FXUS63 KDVN 120434
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1134 PM CDT SAT MAY 11 2013

.SYNOPSIS...
ISSUED AT 308 PM CDT SAT MAY 11 2013

REMARKABLY COLD AND DYNAMIC CANADIAN AIR MASS IS MOVING ACROSS THE
UPPER MIDWEST PRODUCING NORTHWEST WINDS OF 25 TO NEAR 40 MPH WITH
LOTS OF FAIR WEATHER CUMULUS CLOUDS. AREA TEMPERATURES HAVE BEEN
NEARLY STEADY FOR SEVERAL HOURS RANGING FROM THE LOWER 50S NORTH
PORTIONS OF THE FORECAST REGION TO AROUND 60F IN THE FAR SOUTH.
UPPER AIR ANALYSIS SUPPORTS STRONG COLD AIR ADVECTION THROUGH
TONIGHT WITH SURFACE HIGH MOVING OVERHEAD SUNDAY NIGHT WITH NEAR
RECORD TO RECORD LOWS POSSIBLE. UPSTREAM ENERGY SHOWS A TRANSITION
TO ZONAL FLOW AND MUCH WARMER BY TUESDAY WITH NEXT DISTURBANCE
BRINGING SHOWERS AND STORMS MID WEEK.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 308 PM CDT SAT MAY 11 2013

TONIGHT...KEPT FORECAST TEMPERATURES ALMOST THE SAME WITH NEAR TO
BELOW FREEZING TEMPERATURES LIKELY ALONG AND NORTH OF HIGHWAY 30.
NW WINDS WILL DIMINISH TO 4-8 MPH AFTER 4 AM WHICH MAY ALLOW FOR
SOME PATCHY FROST TO FORM AND SINCE MID MAY PLAN ON FROST ADVISORY
WITH TEMPS AOB FREEZING. WINDS WILL BE EVEN LIGHTER FAR WEST
SECTIONS WHICH MAY PRODUCE MORE FROST THAN AREAS TO THE EAST.
SOUTH 1/2 OF THE AREA SHOULD STILL SEE MINS IN THE MID/UPPER 30S.
RECORD LOW OF 32F AT DBQ LOOKS LIKELY TO BE AT LEAST TIED IF NOT
BROKEN AND MLI RECORD SHOULD BE WITHIN A DEGREE OR TWO OF BEING
TIED.

SUNDAY...SUNNY AND VERY COOL FOR MID MAY WITH NW WINDS INCREASING
AGAIN LATE MORNING TO 10 TO 20 MPH. HIGHS LOWER 50S NE TO UPPER
50S SW SECTIONS. THIS WILL BE 15+ DEGREES BELOW NORMAL.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 308 PM CDT SAT MAY 11 2013

.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...
QUIET AND COLD CONDITIONS WILL BE SEEN SUNDAY NIGHT AS THE SFC RIDGE
MOVES ACROSS THE AREA. TEMPERATURES SHOULD QUICKLY DROP AFTER SUNSET
WITH CLEAR SKIES AND LIGHT WINDS. FROST APPEARS LIKELY OVER ROUGHLY
THE NORTHEAST 40 PERCENT OF THE CWFA AND FREEZING TEMPERATURES
CANNOT BE RULED OUT IN THE FAVORED COLD AREAS. HEADLINES FOR FROST
ARE POSSIBLE IN THE NEXT 24 HRS AND A LIGHT FREEZE CANNOT BE RULED
OUT.

RETURN FLOW ON MONDAY WILL ALLOW TEMPERATURES TO WARM CLOSER TO
NORMAL WITH DRY CONDITIONS DURING THE MORNING. THE MODELS HAVE A
RESPECTABLE THETA E GRADIENT MOVING ACROSS THE CWFA DURING THE
AFTERNOON AND EVENING. MOISTURE AVAILABILITY WILL BE THE KEY. FOR
NOW WILL CONTINUE WITH THE SCHC POPS OVER MAINLY THE NORTH/EAST IN
THE AFTERNOON AND THE NORTHEAST/EAST MONDAY EVENING FOR SPRINKLES
AND POSSIBLY SOME SHOWERS.

LATE MONDAY NIGHT THROUGH TUESDAY DRY CONDITIONS WILL BE SEEN WITH
TEMPERATURES CLIMBING ABOVE NORMAL. THERE ARE CONCERNS THAT MAX
TEMPERATURES FOR TUESDAY ARE TOO WARM. FIRST...THE UPPER LEVEL FLOW
IS WEST WHICH IS NOT CONDUCIVE TO GET EXTREMELY WARM. SECOND...LOW
LEVEL LAPSE RATES ARE NOT OVERLY STEEP SO THE WARM AIR ALOFT MAY NOT
BE ABLE TO MIX DOWN AS MUCH. LASTLY...THERE IS NO PRE-EXISTING WARM
DOME TO DRAW FROM TO HELP CREATE EXTREMELY WARM TEMPERATURES. THUS
80 TO 85 MAY BE MORE REALISTIC FOR MAX TEMPERATURES ON TUESDAY WITH
THE WARMEST READINGS IN THE WESTERN CWFA.

TUESDAY NIGHT ON...
THE MODEL CONSENSUS IS SIGNALING A MORE ACTIVE WX PATTERN SETTING UP
FOR THE AREA WITH THE POSSIBILITY OF ORGANIZED NOCTURNAL
THUNDERSTORM COMPLEXES AS A FRONT STALLS ACROSS THE AREA.

THE CURRENT MODEL CONSENSUS HAS TUESDAY NIGHT DRY WITH SCHC POPS FOR
WEDNESDAY.

WED NIGHT THROUGH FRIDAY NIGHT THE MODEL CONSENSUS HAS SCHC/CHC POPS
EACH DAY. TEMPERATURES SHOULD BE NEAR OR SLIGHTLY ABOVE NORMAL.

ON SATURDAY...THE MODEL CONSENSUS HAS CHC POPS BASED ON A REASONABLY
STRONG SHORT WAVE ALOFT MOVING THROUGH THE AREA AND A GOOD FEED OF
MOISTURE FROM THE GULF.

08

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1126 PM CDT SAT MAY 11 2013

VFR CONDITIONS ARE EXPECTED THROUGH SUNDAY EVENING AS HIGH PRESSURE
OVER THE PLAINS MOVES INTO EASTERN IA. PATCHY FROST IS EXPECTED
EARLY THIS MORNING NORTH OF I80 IN EASTERN IOWA.

&&

.CLIMATE...
ISSUED AT 308 PM CDT SAT MAY 11 2013

RECORD LOWS FOR MAY 12...

MOLINE.........33 IN 1960
CEDAR RAPIDS...28 IN 1928
DUBUQUE........32 IN 1969
BURLINGTON.....34 IN 1960

RECORD LOWS FOR MAY 13...

MOLINE.........31 IN 1971
CEDAR RAPIDS...34 IN 1997
DUBUQUE........30 IN 1888
BURLINGTON.....35 IN 1971

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FROST ADVISORY FROM 4 AM TO 7 AM CDT SUNDAY FOR BENTON-BUCHANAN-
     CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-JACKSON-JEFFERSON-
     JOHNSON-JONES-KEOKUK-LINN-WASHINGTON.

IL...FROST ADVISORY FROM 4 AM TO 7 AM CDT SUNDAY FOR JO DAVIESS.

MO...NONE.
&&

$$

SYNOPSIS...NICHOLS
SHORT TERM...NICHOLS
LONG TERM...08
AVIATION...DLF
CLIMATE...NICHOLS