🚀 go-pugleaf

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1132 AM CST WED MAR 6 2013

DISCUSSION...
253 AM CST

PRETTY SURE THERE WILL BE A LOT OF GROUNDHOGS HITTING THE
UNEMPLOYMENT LINES SOON AS THE REGION HAS SEEN ALL FOUR MONTHS OF
WINTER WEATHER JAM PACKED INTO THE PAST 4 WEEKS. FORECAST
CHALLENGES THIS MORNING INCLUDE LAKE EFFECT CHANCES THE NEXT 12-24
HOURS...BIG BUST POTENTIAL ON TEMPS TONIGHT...AND THEN THE WEEKEND
SYSTEM AND THE ASSOCIATED RAIN/SNOW MELT PROBLEMS.

OUR BIG SNOW MAKER IS CURRENTLY MAKING A BEE LINE FOR THE CAROLINA
COAST WITH THE SYNOPTIC SNOW NOW DONE IN OUR AREA. HOWEVER...THE
COLD AIR ADVECTION DOWN THE LENGTH OF THE LAKE IS RESULTING IN A
MARGINAL LAKE EFFECT SET-UP THIS MORNING WITH THERMODYNAMICS
REMAINING SUPPORTIVE OF AT LEAST FLURRIES AND MAYBE SOME LIGHT
SNOW SHOWERS DOWN WIND OF THE LAKE THROUGH TONIGHT. BOUNDARY LAYER
FLOW WILL BE NNE THIS MORNING SENDING THE LE FLURRIES INTO NE IL
BUT THE THREAT SHOULD MEANDER INTO NW IN THIS AFTERNOON AS FLOW
BACKS MORE NORTHERLY.

CLOUD COVER FORECAST THROUGH TONIGHT IS QUITE TRICKY WITH SOME OF
THE GUIDANCE SUGGESTING OVC BREAKING UP...ESPECIALLY WESTERN CWA.
SATELLITE IMAGERY THIS MORNING HAS SHOWN SOME RESPECTABLY SIZED
HOLES BUSTING OPEN IN THE STRATUS...SO ITS NOT OUT OF THE QUESTION
THAT THERE COULD BE SOME CLEARING...ESPECIALLY WEST. FRESH SNOW PACK
WILL LIKELY KEEP BOUNDARY LAYER TEMPS CHILLY TODAY AND LIMIT
MIXING AND EFFECTIVENESS OF MARCH SUN IN MIXING OUT THE CLOUDS SO
HAVE GONE FAIRLY PESSIMISTIC WITH SKY COVER.

UNDERCUT MOS FOR HIGHS TODAY AND TONIGHT OVER WESTERN CWA. IF SKIES
DO INDEED CLEAR OUT TONIGHT...THEN THE LIGHT WINDS AND DEEP PRISTINE
SNOW PACK WOULD SET THE STAGE FOR ONE HECK OF A TEMPERATURE FREE
FALL POTENTIALLY ALLOWING LOWS TO DIP INTO THE SINGLE DIGITS.
CONVERSELY...SHOULD CLOUDS STICK AROUND THEN LOW WILL LIKELY BE A
GOOD 10-15F WARMER THAN GOING FORECAST...SO TEMPERATURE BUST
POTENTIAL TONIGHT IS HUGE. IF/WHERE SKIES DO CLEAR OUT THEN DENSE
FREEZING FOG COULD BECOME AN ISSUE BUT WILL HOLD OFF ON INCLUDING
THAT FOR NOW. HAVE CONTINUED TREND OF UNDERCUTTING MOS TEMPS THURS
THROUGH FRIDAY WITH SNOW COVER LIKELY TO BE A PRETTY SUBSTANTIAL
IMPEDIMENT FOR TEMP RECOVERY.

ANOTHER STRONG STORM SYSTEM LOOKS TO AFFECT THE REGION THIS WEEKEND
BUT THIS ONE WILL COME FROM THE SOUTHWEST AND PUMP "WARM" AND MOIST
AIR NORTH INTO THE REGION AHEAD OF IT. KEPT POPS GENERALLY IN THE
CHANCE CATEGORY THROUGH THE WEEKEND DUE TO UNCERTAINTY AS TO HOW
FAST THIS SYSTEM MOVES. MEDIUM RANGE MODELS ARE FAIRLY PROGRESSIVE
WITH THIS SYSTEM...BUT OFTEN TIMES MODELS SLOW DOWN THE MOVEMENT OF
CLOSED OFF SYSTEMS LIKE THIS SO WOULDNT BE HARD TO ENVISION A
SCENARIO WHERE MODELS TREND SLOWER LATER RUNS. ONCE SYSTEM DOES
ARRIVE SHOULD BE RATHER SLOW MOVING AND COULD RESULT IN DECENT
RAINFALL TOTALS...WHICH WHEN COMBINED WITH WHAT COULD BE A RATHER
QUICK MELT OFF OF THE SNOW PACK COULD RESULT IN SOME HYDRO ISSUES
LATER THIS WEEKEND.

EXACTLY ONE YEAR AGO TODAY WE WERE FLIRTING WITH 70 DEGREE
TEMPERATURES WITH 80S LOOMING LESS THAN A WEEK AWAY. THIS YEAR WE`RE
DIGGING OUT OF ONE OF THE BIGGER MARCH SNOWS THE REGION HAS EVER
SEEN AND NOW MEDIUM RANGE MODELS ARE TRYING TO HINT AT ANOTHER
POTENTIAL SNOW SET-UP SOMEWHERE IN THE REGION EARLY NEXT WEEK. FAR
TOO EARLY TO REALLY EVEN TALK ABOUT THAT POTENTIAL AS MODEL
FORECASTS WILL PROBABLY LOOK TOTALLY DIFFERENT IN A COUPLE DAYS
GIVEN THEIR TENDENCY TO STRUGGLE WITH THESE SORT OF SYSTEMS AT THIS
DISTANCE INTO THE FUTURE. NEVER THE LESS...EVEN HAVING TO MENTION
THE "S" WORD AGAIN NEXT WEEK IS ENOUGH TO LEAVE THIS FORECASTER
CLICKING HIS HEELS THREE TIMES AND CHANTING: "THERE`S NO MARCH LIKE
2012"!

IZZI

&&

AVIATION...

//ORD AND MDW CONCERNS...UPDATED 18Z...

* NORTHWEST TO NORTH WINDS DIMINISHING THROUGH THIS EVENING.
* LINGERING MVFR/VFR CEILINGS CLEARING OVERNIGHT.

PAW

//DISCUSSION...UPDATED 18Z...

FLURRIES AND LAKE EFFECT SNOW ASSOCIATED WITH THE DEPARTING SYSTEM
HAVE PUSHED EAST OF THE TERMINALS AS OF MID DAY. A HIGH PRESSURE
RIDGE WILL BE BUILDING INTO NORTHERN ILLINOIS AND NORTHWEST
INDIANA OVERNIGHT. THE RIDGE WILL HELP TO ERODE THE CLOUD DECK
LINGERING OVER THE AREA THIS AFTERNOON. DEPENDING ON HOW QUICKLY
THE CLOUDS THIN OUT...THERE IS POTENTIAL FOR FG/BR TO DEVELOP
LATER TONIGHT. AT THIS TIME IT APPEARS THAT RFD IS THE MOST
VULNERABLE AND HAVE CONTINUED THE MENTION OF BR IN THAT TAF. LEFT
IT OUT FURTHER EAST DUE TO LOW CONFIDENCE IN TIMING OF THE
CLEARING.

PAW

//ORD AND MDW CONFIDENCE...UPDATED 18Z...

* HIGH CONFIDENCE IN WIND TREND.
* LOW CONFIDENCE IN CEILING TIMING.

PAW

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT THROUGH FRIDAY...VFR.
SATURDAY THROUGH SUNDAY...CHC RAIN.
SUNDAY...CHC RAIN.
MONDAY...CHC SNOW.
TUESDAY...VFR.

BMD

&&

MARINE...
253 AM CST

CONDITIONS SHOULD GRADUALLY IMPROVE TODAY AS LOW PRESSURE OVER THE
EAST COAST MOVES OFF SHORE AND RIDGING OVER THE PLAINS BUILDS EAST
INTO THE GREAT LAKES. THE RIDGE AXIS SHOULD PASS OVER LAKE
MICHIGAN THURSDAY EVENING WITH NORTHERLY WINDS BECOMING
SOUTH/SOUTHEAST BEHIND. ANOTHER AREA OF LOW PRESSURE IS PROJECTED
TO FORM OVER THE CENTRAL PLAINS THIS WEEKEND...LIFTING INTO IN/OH
MONDAY. GUIDANCE IN DECENT AGREEMENT ON THIS LOW DEVELOPING WITH
MODEST TRACK DIFFERENCES GIVEN THAT IT IS STILL ALMOST A WEEK
OUT. SHOULD GUIDANCE PAN OUT THOUGH...EXPECT WINDS TO BECOME
NORTHERLY AGAIN ON THE BACK SIDE OF THIS SYSTEM SUNDAY
NIGHT...INCREASING TO 30 KT WITH GALES A POSSIBILITY.

&&

LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
     UNTIL 3 AM THURSDAY.

&&

$$