Area Forecast Discussion
Issued by NWS Quad Cities, IA IL

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FXUS63 KDVN 270903
AFDDVN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
403 AM CDT SAT JUN 27 2015

.SYNOPSIS...
ISSUED AT 400 AM CDT SAT JUN 27 2015

UPPER LEVEL LOW WAS SITUATED IN LOWER MI WITH THE BULK OF THE RAIN
WELL TO OUR EAST. HOWEVER...THERE IS JUST ENOUGH SURFACE CONVERGENCE
TO DEVELOP A FEW 50DBZ SHOWERS IN NORTHERN IL AS CLOSE AS ROCHELLE
AND OREGON IN OGLE COUNTY. THESE SHOWERS WERE MOVING SOUTHWEST AND
SHOULD TURN MORE SOUTHERLY AROUND THE UPPER LOW. THE FARTHER WEST
THEY GET THE CONVERGENCE WEAKENS SO NOT EXPECTING THE SHOWERS TO
MAKE IT INTO THE DVN CWA. HOWEVER...WILL MONITOR RADAR TRENDS.

MEANWHILE BACK AT THE RANCH...SKIES IN THE CWA WERE CLEAR TO
PARTLY CLOUDY WITH 3 AM TEMPERATURES IN THE UPPER 50S TO LOWER 60S
SO A RATHER COMFORTABLE EARLY MORNING IN PROGRESS.

ELSEWHERE...WATER VAPOR LOOPS SHOW A WEAK VORT MAX DIVING INTO
NORTHERN IA AND ANOTHER STRONGER WAVE IN MANITOBA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT SAT JUN 27 2015

FORECAST FOCUS ON ISOLATED SHOWERS OR STORMS THIS AFTERNOON THEN
THUNDERSTORMS LIKELY IN OUR NW CWA LATE TONIGHT.

TODAY...APPARENTLY MOTHER NATURE WILL NOT ALLOW FOR A DRY DAY AS
OPERATIONAL MODELS SUGGEST ISOLATED SHOWERS AND THUNDERSTORMS
DEVELOPING THIS AFTERNOON...MAINLY NEAR AND WEST OF THE MS RIVER.
THE HRRR DEVELOPS THIS BY EARLY AFTERNOON BUT DIMINISHES THE
ACTIVITY TOWARDS EVENING. I CERTAINLY CAN`T IGNORE THE FACT THAT
THERE WILL BE WEAK CONVERGENCE AT THE SURFACE/LOW LEVELS...THE
CONVECTIVE TEMPERATURE IN THE MID 70S WILL BE REACHED BY EARLY
AFTERNOON AND LAPSE RATES STEEPEN ALONG WITH ENOUGH MOISTURE.
THERE WILL ALSO BE A WEAK VORT MAX TO AID LIFT. THEREFORE...HAVE
ADDED THE MENTION OF NEAR 20 PERCENT POPS FOR THIS AFTERNOON IN
ROUGHLY OUR WESTERN HALF. ANY STORM THAT DEVELOPS COULD CAUSE BRIEF
HEAVY DOWNPOURS BUT EXPECTING ISOLATED COVERAGE WHICH MEANS MOST
AREAS SHOULD REMAIN DRY ALONG WITH MOSTLY SUNNY TO PARTLY CLOUDY
SKIES. THIS WILL BE ANOTHER DAY OF BELOW NORMAL TEMPERATURES...WITH
HIGHS IN THE UPPER 70S. THIS IS BASED ON USING THE SURFACE PARCEL
TRAJECTORY METHOD WITH OUR AIRMASS COMING FROM NORTHERN WI WHERE
THEIR OBSERVED HIGHS YESTERDAY WERE IN THE UPPER 70S.

TONIGHT...SHOULD BE A DRY EVENING BUT THEN ECMWF/GFS/NAM/CANADIAN
ALL SIMILAR IN ROLLING SHOWERS AND THUNDERSTORMS INTO OUR NW CWA
BY LATE TONIGHT. THIS WILL BE AHEAD OF A SIGNIFICANT SHORT WAVE TROUGH
IN THE NORTHWEST FLOW PROVIDING DECENT FORCING. DEEP LAYER SHEAR
WILL BE GRADUALLY INCREASING ALONG WITH PRECIPITABLE WATER INCREASING
TO OVER 1 INCH WHILE SHOWALTERS DROP INTO THE NEGATIVE NUMBERS.
THEREFORE...I HAVE RAISED POPS TO LIKELY IN THE FAR NW BY SUNRISE.
MINIMUM TEMPERATURES WILL BE COMFORTABLE AGAIN BEFORE THE CLOUDS
ARRIVE. LOWS WILL RANGE FROM THE MID 50S FAR EAST TO THE LOWER 60S
FAR WEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 400 AM CDT SAT JUN 27 2015

LITTLE CHANGE NOTED IN OVERALL PATTERN WITH ACTIVE NORTHWEST FLOW TO PERSIST
THROUGH THE PERIOD AND TEMPS NEAR TO BELOW NORMAL.

SUNDAY AND SUNDAY NIGHT...GOOD FORCING WITH SHORTWAVE AND FAVORABLE LEFT EXIT
REGION LIFT QUADRANT OF 80+ KT 300 MB JET DIVING FROM NORTHERN PLAINS
THROUGH MID MISSISSIPPI VALLEY... AND WEAK SURFACE CYCLONE WITH TRIPLE POINT
ALL SUPPORTIVE OF WIDESPREAD SHOWERS AND A FEW STORMS SUNDAY INTO SUNDAY EVE.
THE PRECIPITATION SHOULD CONTINUE SLIDING S/E SUNDAY AM WITH REDEVELOPMENT
DURING THE AFTN. HEAVIEST RAINS 0.5 TO 1+ INCHES SUGGESTED TO FALL ACROSS
PORTIONS OF THE WESTERN AND SOUTHERN CWA VICINITY OF TRIPLE POINT AHEAD
OF SURFACE LOW AS LAYER PRECIPITABLE WATER VALUES SURGE TO NEARLY 1.5 INCHES.
THIS WILL NEED TO BE WATCHED FOR FLASH FLOODING ISSUES ESPECIALLY FOR SOUTHERN
CWA WHICH HAS BEEN HIT HARD WITH SIGNIFICANT RAINS OF LATE AND GROUND IS
SATURATED. CONDITIONAL RISK FOR STRONG TO ISOLATED SEVERE STORMS EXISTS AND
THIS IS DEPENDENT ON AMOUNT OF SOLAR INSOLATION AND SUBSEQUENT DESTABILIZATION.
AT THIS TIME... EXCEPT FOR A WHILE SUNDAY AM MAINLY SOUTH/EAST CWA... I DO NOT
FORESEE A LOT OF SOLAR INSOLATION AND AS SUCH HAVE LOWERED MAX TEMPS A BIT
(WIDESPREAD 70S) LEADING TO LOW THREAT FOR A STRONG TO ISOLATED SEVERE STORM.
HOWEVER... IF MORE SUNSHINE AND SUBSEQUENT INSTABILITY OCCURS THAN CURRENTLY
ANTICIPATING THEN THREAT FOR A FEW SEVERE STORMS WILL INCREASE GIVEN PRESENCE
OF STRENGTHENING 0-6 KM BULK SHEAR 30-40 KTS DURING THE AFTN. PRECIPITATION
SHOULD TAPER OFF FROM NORTHWEST TO SOUTHEAST SUNDAY EVENING WITH SOME CHANCE OF
SHOWERS LINGERING OVERNIGHT IN WRAP-AROUND OVER NORTH AND EAST PORTIONS OF THE CWA.

MONDAY THROUGH FRIDAY... A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL BRING
PERIODIC RAIN CHANCES NEXT WEEK. TRYING TO TIME THESE WAVES REMAINS VERY DIFFICULT
THIS FAR OUT AND UNFORTUNATELY DICTATES THE DAILY BARRAGE OF RAIN CHANCES IN THE
FORECAST EVEN THOUGH WE SHOULD SEE MANY DRY HOURS. TEMPS NEAR TO BELOW NORMAL WITH
HIGHS MAINLY IN THE 70S TO NEAR 80 AND LOWS IN THE 50S/60S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1202 AM CDT SAT JUN 27 2015

RECENT TRENDS AND MODEL GUIDANCE SUPPORT SOME MVFR...AND POSSIBLY
IFR FOG DEVELOPING OVERNIGHT. KCID HAS ALREADY CLEARED OUT...AND
KBRL HAD SOME RECENT RAINFALL...SO I HAVE INCLUDED A TEMPO FOR 2SM
BR. KEPT VSBYS AT MVFR FOR KDBQ/KMLI. THERE IS A LOW PROBABILITY
OF ISOLATED STORMS DEVELOPING SATURDAY AFTERNOON AND EVENING IN
EASTERN IOWA...BUT WITH LOW CONFIDENCE...HAVE OPTED TO LEAVE OUT
OF TAF FOR NOW AND PASS ALONG FOR LATER SHIFTS TO MONITOR.


&&

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

$$

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



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