Area Forecast Discussion
Issued by NWS Little Rock, AR
FXUS64 KLZK 211525 AAB
Area Forecast Discussion...Update
National Weather Service Little Rock AR
1030 AM CDT Fri Apr 21 2017
The area of showers and thunderstorms this morning has focused along
the frontal boundary and upper level shortwave energy over northern
AR. Did have a few strong storms, with strong winds being reported
in spots. This area will continue to move northeast and weaken this
morning. There is another complex of storms, possible severe, over
central OK and moving east. Severe storm watch just issued for parts
of western to west central AR for this complex as it moves east into
AR. Damaging winds will be the main threat. After this storm moves
through AR, another round of storms, possible severe, will be seen
later as the upper system and cold front moves through AR.
Otherwise, clouds and rain will hold temperatures down over the
north, while still reach the 80s over the south. (59)
.Prev Discussion.../ Issued 631 AM CDT Fri Apr 21 2017
Coverage of SHRA/TSRA will remain fairly high over the NRN
terminals this morning into early afternoon hrs...the a break will
be seen. Further south...coverage will be more isolated. A
boundary will drop south through this afternoon...but this
boundary will stall somewhere over the central portion of the
state. However...this front may lift back north...which would
likely impact LIT most as the wind direction may change back and
forth through the day. Overnight...a cold front will move east
through the state...with additional SHRA/TSRA expected
along/ahead of the front.
.PREV DISCUSSION...(ISSUED 338 AM CDT Fri Apr 21 2017)
SHORT TERM...Today Through Saturday Night
The bulk of the SHRA/TSRA activity this morning remains N/NW of the
CWA so far...with just some spotty SHRA over the far NWRN counties
as moisture lifts north of the frontal boundary. This is where the
primary front is located...just south of the MO/AR border.
However...a weakening outflow from Thu evening convection over SE MO
has pushed further S/SW. This mesoscale boundary will gradually drop
south/SW this morning...with mainly a wind shift to the north and
NE. High-res near term guidance puts this boundary around the I-40
corridor by after sunrise.
The main cold front will drop south into central sections of the
state by late this afternoon. Disturbances in the zonal to weak SW
flow aloft will move over NW AR through this afternoon...keeping the
best potential for convection in this region of the state. Only some
isolated to scattered SHRA/TSRA will be seen further south and SE.
Since the area for best precip potential will be north of the cold
front...the primary hazard will be some marginally SVR hail and
locally heavy rainfall. At this time...forecast QPF values through
this afternoon will remain at an inch or so across the far NWRN
counties...with lesser amounts the further east/SE you go. As a
result...only an isolated Flash Flood threat will be possible in
this area. Further south...while the coverage of convection will be
much less...there will be some potential for strong to SVR storms
given higher levels of SFC based instability. Large hail and
damaging winds will be the primary concerns in this region of the
This evening and especially overnight...an upper level shortwave
trough over KS will strengthen as it moves E/SE. As this
happens...SFC low pressure will develop over ERN OK and move ESE
across the state. The cold front that will have dropped to around
the I-40 corridor late this afternoon...will remain nearly
stationary as this low moves east along this original cold front.
The warm sector will remain across the SRN half of the CWA
overnight...with the best potential for seeing any SVR storms in the
evening hrs across WRN/SW AR. Large hail and damaging winds will be
the primary threats with the strongest storms. As the storm system
and new cold front push east by Sat morning...the overall threat for
seeing SVR storms will gradually decrease from west to east.
Additional rainfall amounts this evening through Sat will range from
around another inch across the NRN/NW counties...resulting in
forecast storm total QPF values of 2 to just under 3 inches. Further
south...storm total rainfall amounts will be around 1 inch...with
locally higher amounts.
The new cold front will be east of the CWA...and SFC low NE of the
state by after sunrise Sat...with the threat for strong to SVR
storms and best rain chances moving east of AR. Cooler and drier air
will be seen on the back side of the SFC low as subsidence
intensifies. However...some wrap around moisture will keep some
chances for SHRA and an isolated TSRA in the forecast for parts of
the CWA. These lingering precip chances will gradually decrease by
LONG TERM...Sunday Through Thursday
Low pressure wl be shifting EWD away from AR on Sun, with cooler and
drier air advecting into the state. Some lingering clouds early in
the day over wl give way to plenty of sunshine Sun afternoon as high
pressure blds into the region. Looking for highs in the 60s on Sun,
with lows Mon morning falling into the 40s, when the high is
centered ovr the FA.
The cool down wl be short-lived as the high pressure system moves
EWD and SLY winds return to the Mid-South heading into the middle of
the week. Above normal temps wl prevail thru the rest of the PD.
Small rain chances wl return to parts of AR by Thu as a new storm
system moves into the Plains states.