Severe Thunderstorm Warning 269, NWS Little Rock, AR

Area Forecast Discussion
National Weather Service Little Rock AR
1219 PM CDT Tue Jul 4 2017

.AVIATION...
Greatest coverage of TSRA should be across the northeast third of
the forecast area, through 01z. Expect MVFR ceilings to affect
northern sites for much of the period.

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&&

.PREV DISCUSSION...(ISSUED 938 AM CDT Tue Jul 4 2017)

UPDATE...
Recent mesoscale diagnosis efforts indicate a convectively
enhanced/induced vorticity max, moving northeast near the
OK/AR/MO border, with a small amplitude trough extending towards
the ArkLaTex region. Surface based CAPE of values of >= 2000 j/kg
exist across areas where convective overturning has not occurred
this morning.

Forecasts through 05/06z have been adjusted to account for the
latest trends.

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PREV DISCUSSION...(ISSUED 640 AM CDT Tue Jul 4 2017)

AVIATION...04/12Z TAF CYCLE

Sctd convection wl cont to affect mainly NRN and WRN AR this mrng,
with OCNL MVFR conds where SHRA/TSRA occurs. Confidence in
convective trends later today and tngt still nor clear cut, so
have contd with VCTS in most areas, with PROB30 groups included
ovr the NW half of the FA later tngt. /44/

PREV DISCUSSION...(ISSUED 415 AM CDT Tue Jul 4 2017)

SHORT TERM...Today through Wednesday Night

Scattered convection formed just after midnight acrs parts of Cntrl
AR, mainly S of the AR river. The activity was assocd with a weak
sfc bndry that was aligned fm W to E. Meanwhile, a slow moving MCS
was affecting ERN OK and was just working into NWRN AR just before 3
am. Convection intensity has been gradually weakening ovr the last
few hrs, as noted by warming cloud tops on IR imagery.

The fcst concern once again wl be convective trends thru Wed. The
aforementioned complex of storms/MCV wl cont working EWD today and
tonight, with additional redevelopment of SHRA/TSRA expected by this
aftn. Have kept likely POPS acrs the NRN part of the FA, based on
convective trends noted by the Hi-Res model data. Convection further
to the S wl be more scattered in nature.

The unsettled wx pattern wl cont on Wed as a lingering upper trof
conts working sloly acrs the region. This feature wl again act as a
focus for additional convection, mainly during the aftn and evening
hrs. Cannot rule out some strong storms, but overall severe threat
will rmn marginal at best. Due to the slow movement of the upper lvl
support, locally heavy rainfall wl also be a concern.

LONG TERM...Thursday through Monday

Not a lot of value added changes to the current forecast will be
forthcoming this morning as all medium range models remain in good
agreement with the overall pattern. Much like the past few mornings,
a blend of forecast solutions will be used.

Not to sound like a broken record but the upper pattern will remain
dominated by a sprawling upper ridge over the central rockies and
intermountain west and subsequent downstream troughing. The position
of these features do move around a little but the overall pattern
remains the same.

Strong upper level impulse will be located to the NE of the state
when the period initiates. Isolated to scattered precipitation
chances will continue into early Thursday night before decreasing
somewhat Friday as this impulse moves away and the upper ridge
expands.

With the upper level ridge expanding over the Rockies and the mean
position of the trough moving to our east, Arkansas will be under NW
flow aloft. Additional upper level impulses will move over the state
with at least a mention of isolated to scattered, mainly diurnally
driven convection, justified. Precipitation chances will be aided
slightly over the weekend by a front that backdoors the region from
the NE.

With northwest flow aloft, continuing precipitation chances and the
aforementioned front, temperatures will be a little hard to exactly
pin down. However, they will average close to normal over the course
of the period.

&&

.LZK Watches/Warnings/Advisories...NONE.
&&

Aviation...99

Hazardous Weather Outlook
National Weather Service Little Rock AR
500 AM CDT Tue Jul 4 2017

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-051000-
Boone-Marion-Baxter-Fulton-Sharp-Newton-Searcy-Stone-Izard-
Independence-Johnson-Pope-Van Buren-Cleburne-Jackson-Logan-Conway-
Faulkner-White-Woodruff-Scott-Yell-Perry-Polk-Montgomery-Garland-
Saline-Pulaski-Lonoke-Prairie-Monroe-Pike-Clark-Hot Spring-Grant-
Jefferson-Arkansas-Dallas-Cleveland-Lincoln-Desha-Ouachita-Calhoun-
Bradley-Drew-
500 AM CDT Tue Jul 4 2017

This Hazardous Weather Outlook is for a Large Part of Arkansas.

.DAY ONE...Today and Tonight

Scattered showers and thunderstorms are expected across much of
Arkansas through tonight as an upper level storm system affects the
state. Some storms could produce gusty winds, but organized severe
weather is not expected. Locally heavy rainfall is also possible.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Scattered showers and thunderstorms are possible through the period
with the best chances over the north and northeast sections of the
state. Some decrease in coverage is expected over the weekend as
upper level high pressure starts to build in from the west. Overall,
the chances for hazardous weather are minimal during this period.

.Spotter Information Statement...

Spotter activation is not expected at this time.

&&

Visit NWS Little Rock on the web. Go to http://weather.gov/lzk.

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Special Weather Statement
National Weather Service Little Rock AR
1246 PM CDT TUE JUL 4 2017

ARZ014-023-024-032-033-044-045-041830-
Pulaski AR-White AR-Stone AR-Van Buren AR-Lonoke AR-Faulkner AR-
Cleburne AR-
1246 PM CDT TUE JUL 4 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN STONE...EASTERN VAN
BUREN...WESTERN CLEBURNE...NORTHWESTERN LONOKE...NORTHEASTERN
CONWAY...FAULKNER...SOUTHWESTERN WHITE AND NORTHEASTERN PULASKI
COUNTIES UNTIL 130 PM CDT...

At 1246 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Rocky Hill to near Guy to near Olmstead.
Movement was east at 10 mph.

Wind gusts up to 50 mph will be possible with these storms.

Locations impacted include...
Jacksonville...                   Cabot...
Heber Springs...                  Clinton...
Fairfield Bay...                  Little Rock AFB...
Beebe...                          Greenbrier...
Ward...                           Vilonia...
Austin in Lonoke County...        Greers Ferry...
Quitman...                        Guy...
Rose Bud...                       Damascus...
Enola...                          Twin Groves...
Shirley...                        Mount Vernon...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3584 9224 3538 9204 3488 9186 3490 9229
      3541 9248 3546 9248 3546 9250 3573 9262
TIME...MOT...LOC 1746Z 261DEG 11KT 3567 9251 3534 9237 3498 9223

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