Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
FXUS64 KLIX 300803
Area Forecast Discussion
National Weather Service New Orleans LA
303 AM CDT SAT JUL 30 2016
Bermuda and Great Basin upper ridges remain in place with a weak
surface high across much of the northern Gulf of Mexico. The
weakness in the upper pattern across the lower Mississippi River
Valley continues to allow diurnal development of convection. At
present, there are a very few isolated showers over the coastal
waters, but not much over land. Away from direct marine
influences, temperatures are generally in the 70s, but a sites
with water nearby are in the lower 80s.
See no reason for major changes to previous forecast package.
Upper pattern will slowly shift eastward through Monday, but
ridging not expected to encroach on the area enough to retard at
least scattered diurnal development through Monday. Primary
development over land will start in the 15-17z timeframe each day,
with most, but not all, convection done around 00z. Will continue
to carry low pops for a couple hours beyond 00z each day as a
buffer. Little day to day change in temps expected, although
individual locations could bust if a thunderstorm affects that
location around midday. 35
Great Basin upper high gradually shifts eastward to the Great
Plains by midweek, but it doesn`t appear to get close enough to
the local area to suppress convection significantly. Will continue
previous forecast trends in conjunction with surrounding offices.
Mainly VFR conditions are expected to prevail through Sunday
morning. The exception may be some patchy light fog at KMCB between
08-13z. Isolated to scattered SHRA/TSRA are expected to develop
again with daytime heating, and have placed a PROB30 for TSRA in the
afternoon across all TAF airports in the 06z TAFS. May include a 2-3
hour TEMPO for TSRA with the 12z TAFS. 22/TD
A large and persistent ridge of surface high pressure is expected to
remain over most of the northern and central Gulf of Mexico through
Monday. The southern and western portion of the ridge should erode
Tuesday through the latter portion of next week as generally weak
inverted trough/easterly wave features move west to northwest across
much of the Gulf. Aside from thunderstorms, prevailing winds will
remain generally around 10 knots or less with seas 2 feet or less
through the middle of next week. There could be periods of scattered
thunderstorms with locally stronger winds, a bit more likely today
than tomorrow. The models are not generating much convection at all
over the coastal waters Monday through Wednesday, but there should
be at least isolated showers and thunderstorms around at times.
DSS code: Green.
Activities: Jefferson Parish public safety support for Grand Isle.
Decision Support Services (DSS) Code Legend
Green = No weather impacts that require action.
Blue = Long-fused watch, warning, or advisory in effect or
high visibility event.
Yellow = Heightened impacts with short-fused watch, warning
or advisory issuances; radar support.
Orange = High Impacts; Slight to Moderate risk severe; nearby
tropical events; HazMat or other large episodes.
Red = Full engagement for Moderate risk of severe and/or
direct tropical threats; Events of National Significance.
.PRELIMINARY POINT TEMPS/POPS...
MCB 94 74 93 74 / 50 30 40 20
BTR 93 74 93 75 / 50 30 40 20
ASD 94 78 93 78 / 50 30 30 20
MSY 94 78 91 79 / 50 30 30 20
GPT 91 78 91 78 / 40 20 30 20
PQL 93 74 93 74 / 30 20 30 20