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fxus64 klix 272024 
afdlix

Area forecast discussion
National Weather Service New Orleans la
324 PM CDT Thu Jul 27 2017

Discussion...
generally only small adjustments made to the forecast with this
package as forecast reasoning has not changed.

Another hot and humid day on tap for Friday as high pressure
remains in control of the area weather but begins to be pushed
southward by an approaching cold front. Expect afternoon temps to
top out in the low to mid 90s with dewpoints in the low to mid
70s. This will result in afternoon apparent temperatures of right
around or just over 100 degrees. Don't expect much in the way of
convection tomorrow with the front still well off to the north,
but could start to see some isolated showers and storms sneaking
into the northern parts of the area during the afternoon hours.

Rain chances begin to increase overnight Friday night as the upper
low over the Great Lakes drops southward forcing the surface
front toward the Gulf Coast. Highest rain chances look to be
during the day Saturday with showers and thunderstorms likely for
most of the area. Severe weather set up doesn't look like the
greatest. The best forcing will be to the east of the local area
closer to the actual trough axis. However, a few strong to severe
storms can't be ruled out. The main concerns with this system will
be frequent lightning, heavy rain, and gusty winds.

By Sunday most of the showers and thunderstorms should be located
over the coastal waters and drier air should be filtering into the
area. Because of the high sun angle this time of year, we won't
see too much of an impact on our afternoon temperatures, but the
drier air should have a fairly decent cooling effect on the
overnight lows. Have dropped the forecast lows into the upper 60s
and lower 70s for the northern half of the area which is a few
degrees below normal. South of the tidal lakes, the warm water
temperatures will likely limit the effects of the drier air so
will continue to carry lows in the mid 70s.

Fairly benign weather expected Monday with gradual moisture return
beginning on Tuesday as the old cold frontal boundary begins
meandering back toward the coast and another system begins to
take shape over The Four Corners region. This next system looks to
bring our next appreciable chance of rain to the area during the
second half of next week. Temperatures should remain near or
slightly above normal Tuesday through the end of the forecast
period.

&&

Aviation...
VFR conditions expected to prevail at all terminals next 24-30
hours. Exception may be briefly at kmcb near daybreak on what can
be disputed as either br or haze in stagnant moist airmass for 5sm
MVFR conditions that improve as mixed layer increases.

&&

Marine...
expect continued diurnally forced winds through Friday with light
offshore flow during the late night and early morning hours and a
shift to the west during the day. As a cold front moves toward
the coast Friday night into Saturday, westerly winds will begin
to strengthen to near 15 knots but will weaken as the front moves
through and will remain light behind the front. Scattered to
numerous showers and thunderstorms can be expected along and ahead
of the frontal boundary, with frequent lightning and the
possibility of gale force gusts in some of the stronger storms.
Expect onshore return flow to become established by Tuesday
afternoon.

&&

Decision support...
dss code: blue.
Deployed: none.
Activation: none.
Activities: monitoring river flooding

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 E = full engagement for moderate risk of severe and/or
direct tropical threats; events of National significance.

&&

Preliminary point temps/pops...
mcb 72 93 73 87 / 0 20 40 60
btr 74 93 76 88 / 0 10 30 60
asd 75 94 76 88 / 0 10 30 60
msy 76 93 77 89 / 0 10 20 60
gpt 76 91 76 88 / 10 10 30 60
pql 74 93 74 90 / 10 10 30 60

&&

Lix watches/warnings/advisories...
la...none.
GM...none.
MS...none.
GM...none.
&&

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