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Office: MEG

FXUS64 KMEG 202327

Area Forecast Discussion
National Weather Service Memphis TN
627 PM CDT Tue Mar 20 2018

Updated for 00Z Aviation Discussion.


.PREV DISCUSSION... /issued 457 PM CDT Tue Mar 20 2018/


Updated to add snow chances in northwest Tennessee.


Reports of light snow have been received this afternoon from the
Paris, Tennessee, area and it appears that conditions favor a
short period of light rain and/or snow this evening. Temperatures
aloft have cooled sufficiently to support light snow reaching the
surface despite surface temperatures above freezing. Despite the
light snowfall, ground temperatures should remain too warm to
support much, if any, accumulation on roadways. A quick dusting of
snow on grassy surfaces cannot be ruled out but it will not
result in hazardous driving conditions. A winter weather advisory
does not appear necessary at this time. Conditions will be closely
monitored through the evening.

Updated zones and grids have been sent.



.PREV DISCUSSION... /issued 323 PM CDT Tue Mar 20 2018/

Light rain/drizzle associated with an upper level low will
continue to shift off to the East. A few sprinkles may fall near
the Tennessee River after sunset, but all of the Midsouth should
be dry by midnight. North wind has ushered in cooler air across
the Midsouth. Much of the area saw the warmest temperatures of the
day shortly after sunrise. Temperatures will continue to fall
overnight with frost possible across a large portion of the
Midsouth. Wind overnight may help to limit frost, but sheltered
areas could see at least patchy frost. Freezing temperatures are
possible across a large portion of West Tennessee, especially near
the Tennessee River. Clearing skies may allow temperatures to
fall into the upper 20s though most of the region should remain in
the middle to upper 30s.

Clear and dry conditions are expected tomorrow and Thursday as
surface High pressure and a ridge aloft shift across the region.
Frost and freezing temperatures will be possible again Thursday
morning, but freezing conditions should not be as widespread as we
see tonight into early Wednesday morning. Winds will become
light, so frost may be more widespread. A few clouds are expected
to return to the Midsouth late Thursday as the surface high shifts
over the Appalachians and Southerly winds return to the area.

Temperatures will rebound quickly tomorrow and Thursday. Highs
tomorrow should be in the middle to upper 50s with upper 50s to
mid 60s on Thursday. Above normal temperatures are expected Friday
through the weekend. Rain chances will increase Friday as strong
warm advection sets up across Louisiana and South Mississippi the
Southeast. Early Saturday a weakening surface low will track out
of the Central Plains across Missouri. A warm front will be
oriented across Kentucky into Missouri with a cold front trailing
the surface low stretching down into East Texas. Guidance has the
bulk of the precipitation/thunderstorms to our North along the
warm front with minimal activity along and ahead of the cold
front. WPC has up to two inches of rain in the Missouri Bootheel
tapering off to just about a quarter of an inch in most of North
Mississippi. SPC is not advertising the threat of severe storms
in their extended products. Not confident in the weekend forecast
but rain chances should remain enhanced. Slightly cooler, but near
normal conditions are expected early next week.



00Z TAFs

Lingering MVFR cloud deck at TUP will lift to VFR early in the
period...then believe VFR cigs will linger at all sites through
most of this cycle. Light northwest winds will increase to
10-14kts with higher gusts by 21/15z. Winds diminishing late.



AR...Frost Advisory from 3 AM to 9 AM CDT Wednesday for Clay-
     Poinsett-Randolph-St. Francis.

MO...Frost Advisory from 3 AM to 9 AM CDT Wednesday for Dunklin-

MS...Frost Advisory from 3 AM to 9 AM CDT Wednesday for Alcorn-Benton
     MS-Calhoun-Chickasaw-DeSoto-Itawamba-Lafayette-Lee MS-

TN...Frost Advisory from 3 AM to 9 AM CDT Wednesday for Fayette-

     Freeze Warning from 3 AM to 9 AM CDT Wednesday for Benton TN-



Office: OHX FXUS64 KOHX 202328 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 628 PM CDT Tue Mar 20 2018 .UPDATE... FOR 00Z AVIATION DISCUSSION. && .DISCUSSION... Northwest flow brought cooling temperatures to the Mid-State today, under cloudy skies. By 2 pm, temperatures north and west of Nashville had already dropped into the middle to upper 30s, and some light snow had begun to fall in areas around Clarksville and Dover. Patchy light rain and fog was observed over other areas, where readings remained in the 40s. A Winter Weather Advisory will be in effect from 10 pm tonight through 10 am Wednesday morning for areas along the Highland Rim, north of Nashville, and along the Cumberland Plateau, where the best likelihood for snow and freezing temperatures is forecast to occur. Over the northwest, the snow is expected to taper off this evening, as temperatures near the freezing mark, with snow amounts limited mainly to just a dusting. However, along the Highland Rim and Cumberland Plateau, the likelihood of snow falling late evening and overnight is greatest, and amounts in those areas are expected to average around 1 inch as the temperatures fall to the freezing mark. Locally higher amounts are possible, especially over extreme northeastern Middle Tennessee. The Nashville area will likely see a period of snow tonight. However, the low temperature at Nashville is only forecast to reach 34, so a dusting on grassy areas is about the best to be expected in the immediate Metro area. Can't rule out some slightly higher amounts up to around a half inch over northern and western parts of Davidson County, though. Some lingering light snow will occur along the Cumberland Plateau even into early Wednesday afternoon. However, little additional accumulation is expected. Highs tomorrow will range from the upper 30s along the cloudier Cumberland Plateau, to around 50 along and west of the I-65 corridor. So, any snow that falls tonight and Wednesday morning will be here and gone in a hurry (much like the last event we had). That's one good thing about most March snows. They don't hang around long. Since temperatures across much of the Mid-State are expected to settle to the freezing mark by sunrise Wednesday, a freeze warning has been issued for tonight as well. However, a more substantial freeze is likely on Wednesday night and a freeze warning will likely have to be issued by the midnight shift for that period as well. Right now, it looks like readings in the middle and upper 20s will be likely along the Highland Rim and Cumberland Plateau on Wednesday night. Thursday and Thursday night still look dry. However, an unsettled weather pattern is forecast to prevail from Friday through next Tuesday, with a chance for showers every period. The best chance for rain still looks to be between Friday night and Saturday night, as a weak shortwave passes across the area and pushes a weak cold front southward across the Mid-State. By early next week, an upper level ridge builds to the east of our area, and we come under a more southwesterly flow aloft, and southerly flow at the surface. Clouds will generally keep temperatures from climbing too much through the extended period, with highs mainly in the 50s and 60s Friday, warming to mainly 60s Sunday, Monday and Tuesday of next week. After a chilly night, Thursday night, with lows in the 30s, expect lows to moderate to the 40s and lower 50s thereafter. && .AVIATION... 00Z TAF DISCUSSION. Rain is beginning to change over to snow this evening, and looks to impact KCKV/KBNA/KMQY through around 03Z-06Z. KCSV will have snow chances through the night, and into the morning hours. IFR/MVFR cigs can be expected before cigs improve to VFR first at KCKV by 08Z and KBNA/KMQY by 11Z. KCSV looks to improve from IFR overnight to low MVFR during the day Wednesday. Winds will remain around 10 knots gusting up to 20 knots overnight out of the northwest, and will pick up to be around 15 knots gusting up to 25 knots during the day Wednesday. Winds will calm down Wednesday evening, and be around 5 knots Wednesday night. && .OHX WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 10 PM this evening to 10 AM CDT Wednesday for Clay-Cumberland-Fentress-Jackson-Macon-Overton- Pickett-Putnam-Sumner-White. Freeze Warning from 1 AM to 10 AM CDT Wednesday for Bedford- Cannon-Cheatham-Clay-Coffee-Cumberland-Davidson-De Kalb-Dickson- Fentress-Giles-Grundy-Hickman-Houston-Humphreys-Jackson-Lawrence- Lewis-Macon-Marshall-Maury-Montgomery-Overton-Perry-Pickett- Putnam-Robertson-Rutherford-Smith-Stewart-Sumner-Trousdale-Van Buren-Warren-Wayne-White-Williamson-Wilson. && $$ DISCUSSION......19 AVIATION........Barnwell
Office: MRX FXUS64 KMRX 202338 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 735 PM EDT Tue Mar 20 2018 .AVIATION...An upper trough dropping into the Southern Appalachian Region will rotate in bands of low clouds and an occasional shower throughout the TAF period. At TRI...and to lesser extent TYS...the rain showers will mix with or transition to light snow late tonight before changing back to rain Wednesday morning. Near surface temperatures are expected to remain above freezing for little to no accumulations. CHA should see precip remain as rain through the night. Overall...expect low...occasional MVFR level...clouds over the area for the next 24 hours with occasional reduction in VIS for MVFR to possible IFR conditions. An exception to this may be CHA where some improvement in conditions is expected late in the the TAF period. With the upper trough moving in...surface winds will remain elevated overnight and should become breezy and gusts Wednesday afternoon. && .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...Winter Storm Warning from 8 PM this evening to midnight EDT Wednesday night for Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky Mountains-Southeast Carter- Southeast Greene-Southeast Monroe-Unicoi. Winter Weather Advisory from 1 AM to 11 AM EDT Wednesday for Campbell-Claiborne-Morgan-Scott TN. VA...Winter Storm Warning from 8 PM this evening to midnight EDT Wednesday night for Wise. Winter Weather Advisory from midnight tonight to midnight EDT Wednesday night for Russell-Washington. Winter Weather Advisory from 1 AM to 11 AM EDT Wednesday for Lee. && $$ mjb