Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KDVN 012346
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
646 PM CDT WED OCT 1 2014


.SYNOPSIS...
ISSUED AT 300 PM CDT WED OCT 1 2014

LOW PRESSURE WAS NEAR LAKE WINNIPEG WITH A COLD FRONT SOUTHWARD
INTO WESTERN TX. ANOTHER SURFACE LOW WAS ORGANIZING IN CO WITH A
STATIONARY FRONT EXTENDING INTO NORTHEAST MO AND INTO KY. SOUTH OF
THE FRONT TEMPERATURES WERE IN THE 80S WITH ONLY 50S FROM MN TO MI.
A SHORT WAVE WAS MOVING ACROSS EASTERN IA WHICH HAS KEPT SHOWERS
AND ISOLATED THUNDERSTORMS GOING THIS AFTERNOON...MAINLY IN OUR
SOUTHERN CWA. THIS IS WHERE THE BETTER MOISTURE TRANSPORT/HIGHER
PWAT`S WERE LOCATED. CURRENT TEMPERATURES IN THE DVN CWA WERE IN
THE LOWER 60S TO LOWER 70S.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 300 PM CDT WED OCT 1 2014

TONIGHT...SHORT WAVE WILL EXIT THE AREA TO THE NORTHEAST THIS
EVENING ALLOWING FOR SUBSIDENCE/DRIER AIR ALOFT TO FILTER INTO THE
NW CWA. HOWEVER...IN OUR SE CWA MOISTURE TRANSPORT WILL CONTINUE
TO DEVELOP SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THIS EVENING.
OVERNIGHT...THE LOW LEVEL JET INTENSIFIES AND VEERS FROM EASTERN
KS TO CENTRAL IL. THIS OCCURRING AS MAIN ENERGY STARTS PUSHING
INTO THE PLAINS. THIS SHOULD INCREASE COVERAGE OF SHOWERS AND
THUNDERSTORMS IN OUR SOUTHERN CWA. IN OUR NW CWA WILL HAVE SMALL
POPS FOR SHOWERS BUT THE MAIN ISSUE THERE WILL BE LOW STRATUS/AREAS
OF FOG AND POSSIBLE DRIZZLE AFTER MIDNIGHT...AS LOW LEVEL MOISTURE
CONTINUES TO SPREAD NORTHWARD INTO THE CWA. MINIMUM TEMPERATURES
WILL BE IN THE UPPER 50S TO MID 60S.

THURSDAY...STRONG UPPER LEVEL TROUGH APPROACHING FROM THE WEST
WILL SPREAD LARGE SCALE ASCENT INTO THE MIDWEST...WHICH WILL INTERACT
WITH DEEP MOISTURE AS PWAT`S INCREASE TO OVER 1.70 INCHES. A COLD
FRONT WILL ALSO BE PUSHING INTO CENTRAL IA DURING THE AFTERNOON.
WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED WITH LOCALLY HEAVY
RAINFALL POSSIBLE. THE SEVERE THREAT IS CONDITIONAL ON AMOUNT OF
INSTABILITY THAT DEVELOPS AHEAD OF THE STRONG COLD FRONT. THERE IS
MODERATE DEEP LAYER SHEAR AND STRONG UNIDIRECTIONAL WINDS WHICH
WOULD SUGGEST WIND DAMAGE AS THE MAIN THREAT IF A SQUALL LINE CAN
ORGANIZE. BUT AGAIN THIS WILL DEPEND ON IF THERE IS ENOUGH HEATING.
AS OF NOW SPC HAS A SLIGHT RISK IN OUR SE CWA. WILL CONTINUE TO MENTION
MAXIMUM TEMPERATURES IN THE 70S.

.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT WED OCT 1 2014

THERE ARE A NUMBER OF POTENTIAL WEATHER CONCERNS IN THE LONG TERM
PERIOD. INITIALLY...THE POSSIBILITY OF ONGOING STRONG TO SEVERE
STORMS THURSDAY EVENING...MAINLY SOUTH OF I-80. CONCUR WITH SPC DAY
2 OUTLOOK THAT AMOUNT/COVERAGE OF INSOLATION AND RESULTING POCKETS
OF INSTABILITY WILL BE THE MAIN DRIVER OF SEVERE POTENTIAL. GIVEN
SUFFICIENT INSTABILITY...DECENT SPEED SHEAR PROFILES FAVOR STRAIGHT
LINE WINDS AS THE MAIN ISSUE. AN UNSEASONABLY MOIST AIR MASS COULD
SUPPORT ADDITIONAL HEAVY RAIN...ESPECIALLY ALONG AND EAST OF THE
MISSISSIPPI RIVER. HAVE BUMPED UP POPS ANOTHER NOTCH INTO THE
LIKELY/CATEGORICAL RANGE FOR THURSDAY EVENING.

LOOKING AHEAD...A LARGE UPPER TROUGH IS FORECAST TO IMPACT THE
REGION...ACCOMPANIED BY STRONG COLD AIR ADVECTION AND RATHER ROBUST
WINDS. AFTERNOON TEMPERATURES WILL LIKELY ONLY REBOUND A FEW DEGREES
FROM MORNING LOWS...WITH MOST LOCATIONS HOLDING IN THE 50S. NAM BUFR
SOUNDINGS INDICATE STEEP LOW LEVEL LAPSE RATES TO AROUND
800MB...WITH A FAVORABLE UNIDIRECTIONAL PROFILE. HOWEVER...WINDS AT
THE TOP OF THE MIXED LAYER ARE NOT SUPPORTING A SLAM DUNK WIND
ADVISORY SITUATION. CERTAINLY SOMETHING TO MONITOR FOR LATER SHIFTS.
WITH THE UPPER LOW IN THE VICINITY...SCATTERED INSTABILITY SHOWERS
ARE A GOOD BET...ESPECIALLY NORTH.

FRIDAY NIGHT...WINDS ARE EXPECTED TO STAY UP IN THE 10-15 KT
RANGE...AND HAVE KEEP LOWS A BIT WARMER...MID TO UPPER 30S...WITH
SOME MIXING EXPECTED TO SOMEWHAT OFFSET THE STRONG CAA. THE WINDS
SHOULD ALSO PRECLUDE FROST...ALTHOUGH WIND CHILL VALUES WILL LIKELY
DIP INTO THE 20S AND 30S. SATURDAY NIGHT WILL LIKELY BE THE COLDEST
NIGHT MOST LOCATIONS...AT LEAST IN TERMS OF AMBIENT TEMPS. COOLER
THAN NORMAL TEMPS WILL PERSIST THROUGH THE WEEKEND INTO EARLY NEXT
WEEK...WITH PERIODS OF SCATTERED SHOWERS POSSIBLY SUNDAY AND AGAIN
MONDAY AS A COUPLE OF IMPULSES ROTATE THROUGH THE PERSISTENT
NORTHWEST FLOW. BY TUESDAY/WEDNESDAY...THE ECMWF AND GFS ARE
FAVORING A RETURN TO MORE ZONAL FLOW AND WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 641 PM CDT WED OCT 1 2014

AREAS OF MVFR AND SOME IFR CONDITIONS OF LOW CLOUDS WILL OVERSPREAD
ALL THE TERMINALS THE NEXT SEVERAL HOURS. A SLOW MOVING UPPER
DISTURBANCE WILL RESULT IN EPISODES OF SHOWERS AND THUNDERSTORMS
WITH THE HEAVIEST RAIN REDUCING VISIBILITIES TO 1 TO 3 MILES...POSSIBLY
BRIEFLY LOWER THE NEXT 24 HOURS. WINDS WILL BE LIGHT EASTERLY TO
SOUTHEASTERLY AT DBQ/CID AND LIGHT SOUTHERLY AT MLI/BRL TONIGHT
THROUGH THURSDAY AFTERNOON.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.

&&

$$

SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...RP KINNEY
AVIATION...NICHOLS





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.