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000
FXUS63 KDVN 270818
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
318 AM CDT SUN JUL 27 2014

.SYNOPSIS...
ISSUED AT 315 AM CDT SUN JUL 27 2014

DOPPLER RADAR EARLY THIS MORNING SHOWED A LINE OF THUNDERSTORMS IN
CENTRAL IL ALONG THE FIRST COLD FRONT WHILE ISOLATED SHOWERS AND STORMS
WERE IN EASTERN AND SOUTHEAST WISCONSIN...IN THE DIFFLUENT AREA
CLOSER TO A CLOSED UPPER LOW IN NORTHERN MN. A FEW LIGHTNING STRIKES
WERE ALSO OCCURRING RIGHT UNDER THIS LOW ASSOCIATED WITH THE COLD
POCKET. ACROSS THE DVN CWA PATCHY DENSE FOG WAS OBSERVED ESPECIALLY
IN RIVER VALLEYS AND LOW SPOTS AS DEWPOINTS WERE STILL WELL IN
THE 60S TO LOWER 70S AND WINDS WERE RATHER LIGHT. 3 AM TEMPERATURES
RANGED FROM THE MID 60S TO LOWER 70S.

IN THE MEANTIME...A SECONDARY COLD FRONT WITH MUCH DRIER AIR BEHIND
IT WAS LOCATED FROM NW WI TO NW IA AND WAS MOVING SOUTHEAST. DEWPOINTS
WERE IN THE 50S BEHIND THE FRONT WITH EVEN SOME 40S IN WESTERN SD.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 315 AM CDT SUN JUL 27 2014

FORECAST FOCUS ON A CHANCE OF SHOWERS AND THUNDERSTORMS MAINLY IN
OUR NORTHEAST CWA TODAY...THEN DRY AND COOLER TONIGHT. AMPLIFYING
PATTERN CURRENTLY UNDERWAY OVER NORTH AMERICA WITH A DEEPENING
TROUGH IN THE EAST AND BUILDING RIDGE IN THE WEST.

TODAY...UPPER LOW WILL BE TRACKING INTO LOWER MI THIS AFTERNOON
WITH A STRONG VORT MAX ALSO MOVING INTO SOUTHERN WI BY EARLY THIS AFTERNOON.
WHILE THE CORE OF THE COLD AIR ALOFT WILL REMAIN ACROSS THE GREAT
LAKES THE AMPLIFYING TROUGH IN THE EAST WILL STILL DELIVER SOMEWHAT
COLDER AIR ALOFT INTO THE DVN CWA. THIS WILL BE ESPECIALLY TRUE IN
OUR NE CWA CLOSER TO THE DIGGING TROUGH AND STRONG VORT MAX. STEEPENING
LAPSE RATES SHOULD ALLOW ISOLATED TO SCATTERED INSTABILITY SHOWERS
AND POSSIBLE ISOLATED THUNDERSTORMS LATE THIS MORNING AND AFTERNOON.
I WILL MAINTAIN ONLY 30 POPS AS FORECAST SOUNDINGS INDICATE MOISTURE
WILL BE LIMITED. A SLOWLY DEEPENING SURFACE LOW IN THE GREAT LAKES
REGION WILL TIGHTEN THE GRADIENT LATER THIS MORNING AND AFTERNOON.
MODELS FORECAST 850 MB WINDS FROM THE NORTHWEST AT 40 KNOTS ACROSS
THE CWA AND THIS SEEMS REASONABLE. THIS SHOULD TRANSLATE TO
SURFACE GUSTS OVER 30 MPH. PARTLY SUNNY NORTH TO MOSTLY SUNNY
SOUTH WILL PUSH AFTERNOON TEMPERATURES INTO THE MID 70S TO LOWER
80S. THE SECONDARY COLD FRONT WILL PUSH ACROSS THE CWA TODAY WITH
GRADUALLY LOWERING DEWPOINTS.

TONIGHT...DIMINISHING WINDS THIS EVENING AND PARTLY CLOUDY TO
CLEAR SKIES CAN BE EXPECTED AS A SEASONABLY STRONG HIGH PRESSURE
SYSTEM BUILDS INTO THE NORTHERN PLAINS. DEWPOINTS WILL LOWER INTO
THE LOWER TO MID 50S SO TURN OFF THE A/C AND OPEN UP THE WINDOWS
AGAIN. MINIMUM TEMPERATURES SHOULD BOTTOM OUT IN THE MID TO UPPER
50S WITH A REFRESHING NORTH BREEZE MUCH OF THE NIGHT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 315 AM CDT SUN JUL 27 2014

MEDIUM RANGE DETERMINISTIC MODELS AND ENSEMBLES CONTINUE TO ADVERTISE
HIGHLY AMPLIFIED UPPER PATTERN THROUGH THE PERIOD WITH ANOMALOUSLY
DEEP EASTERN CONUS TROUGH AND WESTERN RIDGE /HEAT DOME/. THIS WILL
KEEP NW FLOW ALOFT LOCKED IN PLACE RESULTING IN PROLONGED PERIOD
OF GENERALLY BELOW NORMAL TEMPS WITH LIMITED MEASURABLE RAIN PROSPECTS
MUCH OF PERIOD. CAN/T TOTALLY RULE OUT A FEW PM SHOWERS THROUGH FIRST
HALF OF WEEK WITH COLD AIR ALOFT AND ANY PERTURBATIONS SHUTTLED DOWN
IN NW FLOW... BUT FEW AND FAR BETWEEN AND EVEN THOSE LOCATIONS THAT
MAY MANAGE TO SEE A SHOWER WILL BE VERY BRIEF AND THUS LITTLE... IF
ANY MEASURABLE RAIN. BETTER CHANCES FOR PM SHOWERS MAY EXIST LATE
WEEK INTO NEXT WEEKEND AS SOME SIGNAL... ALBEIT WAVERING ON POTENTIAL
FOR MORE ROBUST SHORTWAVE ENERGY DIVING DOWN BACKSIDE OF EASTERN CONUS
TROUGH POSSIBLY FORMING CLOSED LOW NEAR CWA.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 315 AM CDT SUN JUL 27 2014

EXPECT PERIODS OF IFR CIGS/VSBYS OVERNIGHT AT KBRL/KMLI...WITH
MVFR VSBYS AT KDBQ/KCID. A FRONTAL BOUNDARY WILL MOVE THROUGH THE
REGION TOWARD DAYBREAK...LIKELY HELPING MIX OUT THE FOG. THE WIND
WILL BECOME GUSTY DURING THE LATE MORNING AND AFTERNOON. ISOLD
SHOWERS WILL BE POSSIBLE IN THE AFTERNOON...MAINLY AT KDBQ.

&&

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

$$

SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...05
AVIATION...HAASE