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

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FXUS64 KLIX 212122

Area Forecast Discussion
National Weather Service New Orleans LA
422 PM CDT Fri Jul 21 2017

.SHORT TERM (Tonight through Monday)...
The central Gulf coast region will be under the influence of a
broad mid/upper level low that will be moving west across the
northeast and north central Gulf of Mexico tonight, and towards
the western Gulf coast region over the weekend. Higher moisture
content returned today with precipitable water (PW) values up to
the 1.9 to 2.0 inch range, and these values are expected to
persist through the weekend with some higher values between 2.0
and 2.25 inches south of Lake Pontchartrain on Saturday and across
the forecast area Sunday. This will support the forecast of good
scattered coverage of showers and thunderstorms Saturday with a
bit higher coverage expected on Sunday. Locally heavy rainfall and
some stronger thunderstorms with gusty winds and frequent
lightning will be possible. Temperatures are expected to trend
near to slightly below the seasonal averages.

High pressure is then expected to rebuild across the Gulf of
Mexico on Monday which should lower the rain chances substantially
and allow the temperatures to spike back to very warm levels.

.LONG TERM (Monday night through Friday night)...

A general area of deep layer high pressure is expected to prevail
across the Gulf, however the models indicate a series of
shortwaves moving southeast from the northern plains into the
northeast states. This may break off a lower latitude shortwave
trough/weakness over the southeast states Tuesday that should be
progressive and move east towards the south Atlantic coast by late
Wednesday, allowing deep layer high pressure to rebuild quickly.
This pattern will be generally be mostly dry (mainly isolated
convection at best) and very warm with above normal temperatures.


Isolated to scattered showers and thunderstorms continue to
occasionally impact some of the terminals, but should start to
decrease in number going towards evening. Nocturnal convection
will be a possibility especially south of Lake Pontchartrain later
on in the night. Otherwise expect VFR conditions with afternoon
convection once again for Saturday. 13/MH


High pressure over the Gulf of Mexico is expected to result in
mostly south to west winds around 10 knots or less through the
weekend, then an occasional tightening of the pressure gradient
may cause winds to rise into the 10 to 15 knots range at times
over portions of the area early next week. 22/TD


DSS code: Green.
Deployed: None.
Activation: None.
Activities: Monitoring Convective trends.

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.


MCB  74  90  73  89 /  30  40  20  60
BTR  75  91  75  89 /  30  50  20  60
ASD  76  92  75  90 /  30  40  20  60
MSY  77  91  76  90 /  30  40  20  60
GPT  76  91  77  89 /  30  40  20  50
PQL  74  91  74  89 /  30  40  30  50



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