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Area forecast discussion 
National Weather Service Peachtree City Georgia
623 am EST Tuesday Mar 3 2015




Previous discussion... /issued 315 am EST Tuesday Mar 3 2015/

Short term /today through Wednesday/...
weak frontal boundary looks to be situated across the southern County warning forecast area
this morning and can mostly be found by the decent dewpoint
gradient. Some patchy fog is noted south of the boundary...but the
lower ceilings and visibilities remain just south of the County warning forecast area. Do think some of
the fog will advect northward...mainly along and south of a Columbus
to Macon line. Further north...a light northerly wind has kept
things a little more mixed with larger temperature/dewpoint spreads. Low
clouds/fog/drizzle may be a little harder to get north of the weak
front.

Recent runs of the hrrr have been pretty consistent with bringing a
more organized area of light to moderate rainfall across north and
central Georgia towards sunrise. This solution seems reasonable...as
water vapor and rap40 500mb analysis shows a shortwave approaching
northern Georgia. Low level winds are expected to turn more easterly
north of the weak front today as a wedge tries to build in from the
northeast. So...probability of precipitation should be the highest across the far north with
light rain and/or a prolonged period of drizzle is likely for the
late morning and afternoon. Along and south of the
boundary/wedge...precipitation should be more hit and miss and chance or
slight chance probability of precipitation should be sufficient. Would not be surprised to
hear a rumble or thunder or two later this afternoon...but chances
remain too small to mention at this time. A more organized area of
precipitation is expected by Wednesday morning as a cold front
approaches from the northwest.

The temperature forecast remains very tricky again today. Areas
south of the weak boundary will remain in warm southerly flow. Areas
north will remain N/NE. If the boundary moves a little northward
before washing out overnight...then temperatures across the central portion
of the forecast area have the potential to bust...again. Mild
conditions expected overnight as models continue to erode The Wedge.
Warmer than normal temperatures likely on Wednesday ahead of the
front...even near 80 in the far South County warning forecast area with lower 70s in the
metropolitan area.

Nlistemaa

Long term /Wednesday night through Monday/...
extended forecast period starts out with a lot of uncertainty as
medium range models continue to trend a bit slower with the push of
cold air into northwest Georgia...and a bit warmer as well. Mav MOS
lows Thursday morning remain at or above freezing now and met MOS
lows remain all above. Even so...if we are closer to the cooler mav
at the MOS sites we should see some areas at or a degree or two
below freezing before sunup Thursday in the far north. This fits the
trends in the ice accumulation forecasts from the westward as well which
are pulling light accumulations back further to the northwest. I
have adjusted gridded weather to show likely rain with chance
freezing rain and sleet at the cooler grid points and likely rain
with chance sleet at the more borderline grid points from midnight
through sunup...with lingering chance/slight chance for a mix at the
cooler points in the far north through the day as better probability of precipitation push
south and east of that area. With the quantitative precipitation forecast values forecast and
relatively warm antecedent conditions my total ice accumulation
grids are generally .10 inch or less which also lines up well with
westward forecast values. With the trend toward at least a slightly
warmer scenario I am not near the confidence level needed to go out
with a winter weather watch at this point...but we will need to keep
a close eye on trends through the next couple of forecast cycles.

Looks cool but generally dry for Thursday night/Friday but
temperatures rebound nicely into the weekend as generally zonal
upper-level flow pattern keeps the better cold air north and west of
the forecast area. Hard to go above slight chance/low chance for
probability of precipitation through any of the remainder of the extended forecast period as
no significant focus for better...more organized...precipitation
chances are evident in the persistent zonal flow.

20

&&

Aviation...
12z update...
old frontal boundary situated across south Georgia this morning. The
boundary will eventually wash out overnight. Wedging has started
to build in across the NE portion of the state as the easterly
winds have become established. Regional radar shows some patchy
light rain/heavy drizzle making its way across the northern
terminal sites...in association with a passing shortwave. Low ceilings
should continue for much of the day...however a brief period of
MVFR is possible during the late afternoon. IFR expected again
overnight. East winds will also begin to shift to the S/SW
overnight as a cold front approaches from the northwest.



//Atl confidence...12z update...
medium confidence all elements.

&&




Preliminary point temps/pops...
Athens 51 49 72 54 / 60 50 40 70
Atlanta 59 55 70 45 / 60 40 50 70
Blairsville 49 47 62 42 / 70 70 70 70
Cartersville 54 52 69 40 / 60 50 60 70
Columbus 74 60 75 54 / 30 20 30 60
Gainesville 49 47 67 47 / 60 50 50 70
Macon 66 58 77 59 / 30 20 20 50
Rome 57 53 68 37 / 60 60 70 70
Peachtree City 62 56 71 48 / 50 30 40 70
Vidalia 68 62 79 62 / 30 20 10 20

&&

Ffc watches/warnings/advisories...
none.
&&

$$

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