Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
FXUS64 KLIX 012049
Area Forecast Discussion
National Weather Service New Orleans LA
349 PM CDT SAT OCT 1 2016
Upper low over northern Indiana this afternoon with upper ridging
over the Rockies. Weak upper trofs over the central Gulf of
Mexico and central Texas. At the surface, high pressure is
centered south of Memphis, with a stationary frontal boundary over
the Gulf of Mexico about 80 miles south of the Louisiana coast.
Scattered clouds across the area with temperatures generally in
the lower to middle 80s and dew points in the 50s.
Not much real change in short term forecast scenario. Trof over
Texas will move eastward over the next 24 hours. Moisture is
rather sparse and anticipate that all we should see over land with
this shortwave is a slight increase in clouds during the day on
Sunday, with any convection staying well offshore.
As Indiana upper low gradually moves into New England by Monday
night and Tuesday, shortwave ridging will build briefly into the
area during that time. Dry air will remain in place and little or
no precipitation is anticipated through Tuesday.
Considering dry air is in place, will trend toward cooler end of
low temperature guidance and warmer end of high temperature
guidance through Tuesday. This will put highs in the mid and upper
80s through Tuesday with overnight lows near normal. 35
Upper ridging moves to the eastern third of the country by
Thursday. Question then becomes how the upper pattern is affected
by Hurricane Matthew during the middle and end of next week. Front
associated with the next upper trof moving out of the Rockies
should move into the area around Thursday or Friday, which is
somewhat slower than previous runs. For now will hold on to
previous POP forecast which will give the best chance of rain on
Thursday. Even then, we are only talking 20-30 percent at best.
Temperatures should remain above normal until after the cold
frontal passage at the end of the week. 35
Dry air should continue to keep prevailing VFR conditions through
Sunday. There may be temporary periods of 3-5nm VSBYS for a few
hours late tonight, mainly at KHUM. 22/TD
Well defined old stationary frontal boundary persists over the
offshore Gulf waters greater than 60 nautical miles from shore. As
mentioned in the previous discussions, there continues to be a
"kink" northward along an inverted trough over the west central to
northwest Gulf of Mexico in a broad area estimated between 92 to 94
W longitude. A well defined shortwave trough (in water vapor
imagery) over central Texas to northeast Mexico, associated with an
area of mid to upper level divergence near and in advance of the
feature, is expected to move east-southeast across the western to
central Gulf coast region along with a series of weaker embedded
shortwaves through Sunday night. This will allow some slightly
deeper moisture return over the western offshore waters along with
isolated to locally scattered showers and thunderstorms Sunday into
Sunday night, however the high pressure and very dry air to the
north will be stubborn to become dislodged. The main impact besides
the convection will be a baroclinic zone with higher winds likely
rising to near 15 knots over offshore waters west of Southwest Pass
Sunday and Sunday night with seas building up to around 3 feet.
The inverted trough and areas of stronger winds associated with it
are expected to move west early next week with the ridge high
pressure expanding over the marine areas. Winds and seas should ease
somewhat over western waters, but will have to watch the eastern
waters where a tightening pressure gradient could lead to some
stronger winds and higher seas by mid to late in the week as
hurricane Matthew moves into the vicinity of the Bahamas. 22/TD
DSS code: Green.
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 58 84 60 87 / 0 0 0 0
BTR 59 86 62 87 / 0 0 0 0
ASD 60 85 63 87 / 0 10 10 0
MSY 69 85 67 86 / 0 0 10 0
GPT 63 84 65 87 / 0 10 10 0
PQL 58 85 62 88 / 0 0 10 0