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

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS64 KLIX 252108

Area Forecast Discussion
National Weather Service New Orleans LA
408 PM CDT Tue Apr 25 2017

Air mass modification underway with gradient tightening to the
west of the forecast area at this time. Low pressure system is
developing with frontogenesis taking place in west Texas. Onshore
flow gradient winds will be increasing steadily for the next 24-30
hours with system`s approach. The bulk of the dynamics will be
lifting northward upon the front`s arrival into the forecast area
with the severe weather threat diminishing, though SPC Marginal
risk seems warranted for the western portions in the evening
hours. Time of greater impacts still appears between 9 pm and 3 am
Wed night. Drier conditions take hold Thursday with weak wake high
pressure that will relax rather quickly in response to next
developing system in the High Plains by later in the day Thursday.

Plains system advances eastward with upper trough digging Sunday.
This brings a much stronger front with deeper moisture and
instability to cause large concerns for the several outdoor events
taking place in the region this weekend. Will be showing
categorical PoPs for Sunday late afternoon into the evening hours,
with severe thunderstorm potential in play for QLCS activity.
Cooler continental air builds into the region for Monday that
sustains into Tuesday and early Wednesday of next week before yet
another system moves into the Mississippi Valley. Went with
consensus guidance temps and PoPs for the first half of the
forecast run and trended into GFS solution with some smoothing
with neighboring offices on PoPs for the latter half of the
forecast cycle. 24/RR


VFR conditions will persist through around 10z tomorrow.  After 10z,
lowering ceilings to between 1500 and 2500 feet will produce MVFR
restrictions at several airports.  KBTR, KHUM, KHDC, and KMCB will
be most impacted by these ceilings between 10z and 18z.  There could
be a brief period of light fog and possibly IFR ceilings at KMCB
around 12z.  After 18z, some daytime mixing should break up the
lower cloud deck allowing for a mix of MVFR and VFR conditions
during the afternoon hours.  Winds will turn gusty from the south by
12z tomorrow.  South winds of 15 to 20 knots with higher gusts can
be expected. 32


An increasing pressure gradient over the coastal waters related to a
deepening low pressure system in the Southern Plains will result in
exercise caution conditions spreading from west to east tonight and
tomorrow.  There could be a window for conditions to increase into
Small Craft Advisory range tomorrow afternoon and evening.  Seas
should also increase from 1 to 3 feet to 4 to 6 feet over the open
Gulf waters by tomorrow afternoon.  These rough conditions should
persist through Thursday morning before easing as the low pulls out
of the region and high pressure settles in.


DSS CODE...Green.

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.


MCB  60  84  57  83 /   0  10  70  10
BTR  63  85  58  84 /   0  10  60  10
ASD  62  83  65  85 /   0   0  60  20
MSY  64  84  66  84 /   0   0  50  10
GPT  66  79  70  83 /   0   0  50  30
PQL  61  80  67  84 /   0   0  50  40




32 is the U.S. government's official web portal to all federal, state and local government web resources and services.