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fxus64 klix 141640 
afdlix

Area forecast discussion
National Weather Service New Orleans la
1040 am CST Thu Nov 14 2019

Update...
made some short-term updates to grids to handle current radar
trends on rainfall coverage. This includes hourly pops which shows
a couple of hours of 70-80% this afternoon confined to the period
when the conveyor axis passes through the area. This may appear to
be a high rain day, but should remain light stratiform for the
most part except for elevated high based convection this
afternoon. Temperature are actually warming faster than indicated,
into the mid 50s most places this morning, so altered the diurnal
temperatures to align with current trends.

&&

Aviation...
18z tafs will remain essentially VFR for ceilings and visibility
though there will be periods of r- and rain shower- as surface low
traversing the central Gulf provides an isentropic lift layer over
the central Gulf states. A moist conveyor axis (elevated
convergence axis similar in orientation to a surface cold front)
will move through kmsy/knew/khum, possibly the other locations,
this afternoon for a 1-2 hour window of rw, but should have
limited impact on vis or cig. General clearing overnight for VFR
ceiling and visibility unlimited conditions later tonight all terminals.

&&

Previous discussion... /issued 409 am CST Thu Nov 14 2019/

Short term...far warmer than 24 hours ago but still below normal
and this will continue to be the case through the upcoming weekend.
At 9z radar showed quite a few echos however most of this is likely
not reaching the ground as pws from last nights sndg was still at
0.27". This is rather dry and will take a while to moisten up.

As for the forecast the next 24 hrs will be the most challenging
till Sunday. Main concern, which won't really be that impactful,
is rain today and tonight. As mentioned earlier the column is
quite dry and will take some time to moisten up. A nice little S/W
is moving through northern Mexico towards southern Texas. This wave
will merge with a stronger S/W dropping across The Rockies as it
moves towards the lower MS valley. Ahead of these two features
weak isentropic lift will continue to develop scattered showers.
Much of this rain will continue to struggle to reach the ground
through the day however a few hundredths at best can not be ruled
out especially across the southern half of the area(along and
south of the 10/12 corridor). The best chance for measurable rain
across the northwest may be late this afternoon and tonight as the
northern stream S/W approaches. This feature will be stronger and
may have a better chance of squeezing out what available moisture
is in place. That all said have backed down on pops a tad mainly
because not really sure if everyone will measure. Yes very light
rain is likely over a good portion of the area but whether it
amounts to anything appreciable is in question. Even if rain
doesn't quite reach the ground for some areas it will still be an
ugly dreary day with broken to overcast skies and cold
temperatures, highs around 20 degrees below normal.

Tonight's S/W will continue to swing southeast and is expected to
deepen and close off just to our east. Drier air will be reinforced
but highs on Friday will actually be a touch warmer thanks to what
should be full sun. Lows may drop to near freezing once again Friday
night mainly across sela along and north of I-12. This weekend will
remain dry with temperatures remaining below normal but temps will
moderate a little with highs by Sunday in the lower to mid 60s.

Long term...overall the forecast looks fairly quiet going into next
week however there are some questions mainly Sunday night and Monday
morning. Temperatures will continue to moderate with near normal
temps possible around Wednesday. The biggest question in this part
of the forecast is rain chances overnight Sunday and early Monday
morning. Most of the guidance is suggesting a faster weaker S/W
Sunday night. This would suggest a dry forecast however there are a
few suggesting a slower more potent S/W and this again could squeeze
out what available moisture is there for some showers. Given the
ensembles are quite pessimistic with this feature have opted for a
mostly dry forecast and sticking with 10-20% pops at best for now.
Even if the S/W is slower and stronger the really won't be anything
of concern as light rain at best would be expected, maybe around
morning rush hour. /Cab/

Marine...as previous forecaster mentioned winds are expected to
bounce back up as a weak sfc low develops in the Gulf combines with
the large area of high pressure across the plains. This will tighten
the gradient to allow for winds to increase this afternoon and more
so tonight across much if not all of the open waters along with the
Breton and chandeluer sounds. Have already issued an scy for the
waters east of the MS river beginning this afternoon and then
expanding to include the rest of the previously mentioned waters
tonight. Winds may remain on the breezier side through Friday night
but should finally begin to back down as high pressure builds across
the area for the weekend. /Cab/

Aviation...mostly VFR category conditions will prevail at the
terminals during the taf forecast period. However, occasional light
rain developing Thursday morning and continuing through the much of
the afternoon will yield MVFR vsbys at times. /11/

Decision support...

Dss code: blue.
Deployed: none.
Activation: none.
Activities: Small Craft Advisory

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; marginal risk severe or excessive rain.
Yellow = heightened impacts with short-fused watch, warning or
advisory issuances; radar support for slight risk severe
or excessive rain.
Orange = high impacts; enhanced risk severe; nearby tropical
events; hazmat or other large episodes.
Red = full engagement for moderate to high risk of severe and/or
excessive rainfall, or direct tropical threats; events of
National significance.

&&

Preliminary point temps/pops...
mcb 48 35 55 31 / 30 50 0 0
btr 50 36 55 32 / 20 30 0 0
asd 52 37 58 32 / 70 30 0 0
msy 53 42 57 40 / 80 30 0 0
gpt 52 40 56 36 / 60 70 0 0
pql 53 39 60 33 / 40 70 10 0

&&

Lix watches/warnings/advisories...
la...none.
GM...Small Craft Advisory from 6 PM this evening to 6 PM CST Friday
for gmz550-552-570-572.

Small Craft Advisory until 6 PM CST Friday for gmz536-538-555-
557-575-577.

MS...none.
GM...Small Craft Advisory from 6 PM this evening to 6 PM CST Friday
for gmz552-570-572.

Small Craft Advisory until 6 PM CST Friday for gmz538-555-557-

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