Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

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000
FXUS64 KLIX 242045
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
345 PM CDT Fri Mar 24 2017

.SYNOPSIS...
Latest upper air and IR satellite imagery showed a low over the
Texas Panhandle with dry air entrainment into the south and east
side of the low. In addition, ahead of the leading edge dry air
cooler cloud tops from convection was over North Central Texas to
Southwest Missouri. Isotach analysis at 250mb revealed a 110 to
120 jet max at the base and front side of the low or over West
Texas to south central Oklahoma.

Surface analysis showed a 1003mb over Texas Panhandle off the
Caprock with a tight pressure gradient over Red River Valley and
Mid and Lower Mississippi. South to southeast flow was present
across the same area.

&&

Deep surface low will continue to move east southeast along the
Red River Valley through tonight. Surface winds are expected to
weaken this evening but remaining breezy overnight. Because the
system is vertically stacked with occlusion some slowing east will
likely occur through Saturday. Ergo, the timing of the initial
line of convection will enter the extreme west zones after
midnight. Low level southeast to south flow and southwest flow
aloft will increase 0-3km helicity values 250 to 400 m/s later this
evening, higher values across the northwest and north zones.
Isolated to scattered storms that do develop will have a chance to
yield rotating storms and possibly a tornado or two with the
initial convection, mainly across the northwest parts of the
forecast. Cape values do increase with values of 700 j/kg across
Southern Mississippi to 1500 j/kg along the Louisiana.

With the upper level disturbance rotating southeast through the
forecast area overnight, 500mb temps will dip to -17F across
northwest zones early Saturday and spread east through Saturday.
As a result, a few to several storms may contain hail. As for
now, damaging winds and secondary threat of tornado or two may
occur early ahead and along the squall late tonight into early
Saturday morning. Hail storms and possibly damaging winds are
possible in scattered to numerous storms Saturday morning through
Saturday afternoon.

While no frontal passage is expected with the storm system, mid
moisture will be displaced east and precipitable water values
decreasing to 0.75 to 1 inch across the forecast area on Sunday.

LONG TERM...

A short wave will rake across the Mid South on Monday yielding a
few storms, and few of these storms across the north half of the
forecast area could be strong but below severe limits Monday and
Monday night.

Meanwhile in the latter part of the forecast, a very strong
system will approach the Lower Mississippi Valley late Wednesday
into Thursday. While 6 to 7 days away, the pattern does support a
round of strong to severe across the forecast area late next
week.

&&

.AVIATION...

MVFR ceilings will persist through at least 18z with some
improvement into VFR range after 18z tomorrow.  Southerly winds
should decrease to around 15 knots after 00z and continue at this
level through 00z tomorrow.  The threat of convection continues, and
have TSRA wording in place from 12z through 18z.  The convective
threat will decrease at most terminals after 18z, but could persist
around KBTR and KMCB into the afternoon hours. 32
&&

.MARINE...

Small craft advisory conditions with winds over 20 knots and rough
seas of over 7 feet will persist into tonight.  Some relaxing of the
winds is expected tomorrow and tomorrow, but small craft should
continue to exercise caution. The pressure gradient over the Gulf
will continue to weaken tomorrow and Sunday as high pressure
overspreads the coastal waters. Expect to see southerly flow of 10
to 15 knots and seas of 3 to 5 feet by Sunday, and then to see
these conditions persist through Tuesday. Another fairly strong
low pressure system should then bring another round of small craft
conditions to the waters for Wednesday and Thursday. 32

&&

.DECISION SUPPORT...
DSS CODE...Orange.
DEPLOYED...None.
ACTIVATION...None.
ACTIVITIES...Monitoring Severe Weather Potential.

Decision Support Service (DSS) Code Legend:
GREEN  = No weather impacts that require action
BLUE   = Long fused Watch/Warning/Advisory in effect or high
         visibility event
YELLOW = Heightened impacts with short fused
         Watch/Warning/Advisory issuances; Radar support
ORANGE = High Impacts - Slight to Moderate risk of severe weather;
         Nearby tropical events, HAZMAT or other large episodes
RED    = Full engagement for moderate risk of severe weather; Direct
         tropical threats; events of national significance.
&&


.PRELIMINARY POINT TEMPS/POPS...
MCB  65  75  60  81 /  60  70  20  10
BTR  66  78  60  82 /  60  70  20  10
ASD  66  77  63  81 /  30  70  20  10
MSY  68  78  66  82 /  30  70  20  10
GPT  66  74  64  78 /  20  70  20  10
PQL  65  75  63  79 /  10  70  40  10

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Wind Advisory until 7 PM CDT this evening for LAZ034>037-039-040-
     046>050-056>072.

GM...Small Craft Advisory until 7 PM CDT this evening for GMZ530-532-
     534-536-538-550-552-555-557-570-572-575-577.

MS...Wind Advisory until 7 PM CDT this evening for MSZ068>071-077-
     080>082.

GM...Small Craft Advisory until 7 PM CDT this evening for GMZ532-534-
     536-538-550-552-555-557-570-572-575-577.

&&

$$



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