Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
FXUS64 KLIX 260858
AREA FORECAST DISCUSSION
National Weather Service New Orleans LA
358 AM CDT MON SEP 26 2016
Upper level ridge that encompassed most of the southeastern United
States continues to compress and weaken as a trough tracks east
across the high plains towards the Great Lakes. The weakening of the
ridge and lowering of surface pressure will allow for scattered
convection to develop and become slightly more widespread today.
Surface analysis shows a cold front associated with the upper trough
tracking southward across central texas and central Arkansas. This
boundary will track across northern Louisiana, entering northwestern
portions of the CWA late morning into the early afternoon hours.
Slight lift from this boundary will enhance shower and thunderstorm
coverage this afternoon, so have pops in the 30 to 40% range. The
cold front will slowly sag southward towards the Gulf of Mexico
tonight but stall in the vicinity of the coast as the upper low to
the north stalls over its Great Lakes position. A few showers and
thunderstorms may develop Tuesday on the back side of the front with
most of the activity along the coastal areas.
The upper low to the north will shift southward to the Ohio River
Valley before tracking northeast towards NYC from Wednesday through
the weekend. This will result in a dry forecast as continental air
mass is drawn south to the Gulf Coast. This coldest air since last
spring is expected from midweek onward with Friday looking like the
chilliest of those days as a secondary surge of cooler air moves in
late Thursday. Expect mid 50s to lower 60s Friday morning and highs
barely reaching 80 degrees that afternoon. A gradual moderation will
ensue this weekend as the trough lifts out and 500mb heights begin
AVIATION... Outside of convection this afternoon and this evening,
VFR conditions are expected for taf sites through Tuesday 12z. Will
use PROB30 for TSRA between today 21z through Tuesday 03z. A cold
front will push through establishing a north wind of 5 to 10 knots
late this afternoon and evening for most taf sites, 10 to 15 knots
at KNEW. A VFR ceiling may develop after 00z tuesday and lower to 3
to 4kft by 12z tuesday. 18
Last 12 to 18 hours before cold front moves off the coast for some
cold air advection influences over the warm waters for a period of
gustiness tonight and Tuesday. Guidance winds are below advisory
criteria but gusts may, at times, reach 20 knots for a couple of
hours before Tuesday morning. High pressure with settle over Texas
Tuesday through Wednesday and maintain a light north flow. A
secondary surge will push through Thursday into Thursday night and
increase north winds. At this time, wind speeds should remain
below small craft advisory criteria. 18
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 91 66 83 60 / 30 20 10 10
BTR 91 67 85 64 / 30 20 10 10
ASD 91 71 86 67 / 30 20 20 10
MSY 92 75 86 71 / 30 20 20 10
GPT 90 73 86 68 / 30 20 20 10
PQL 89 72 87 65 / 30 20 20 10