Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus64 klix 221421 
afdlix

Area forecast discussion
National Weather Service New Orleans la
821 am CST Wed Feb 22 2017

..sounding discussion...
Winds are northerly behind the upper low this morning and become
more northwest with height. Overall it is a dry and stable
profile, though there is a weird feature aloft from the back side
of the upper low. The 500 mb temp is -8 c, which is the Max for
the day in the Storm Prediction Center climatology. Last night it was -16 c. Maybe
the inversion at 480 mb is from subsidence due to the 100 kt jet
associated with the closed low as it becomes cut off. The feature
is on lch and Jan as well. This has helped lead to sunnier skies
than were expected so far this morning and will likely continue
much of the day.

Krautmann



&&



Previous discussion... /issued 323 am CST Wed Feb 22 2017/

Short term...
cloudy conditions will be in and out today. A few of these may
even contain some very light rain over coastal Mississippi later
today. The 10% across the area will take up for this. Patchy fog
will be possible Friday morning before the upper low finally
weakens further and moves southeast. This will allow another cold
front to move through Friday night which will clear things out
and bring some cool air. There is enough forcing with this front
to develop some shower activity along the entire boundary and this
may have to be bumped up to chance category. There are even some
stability parameters that are unstable enough to show the
possibility of some thunderstorms along this boundary developing
as it moves through. Isolated showers along this boundary will be
continued in this fcast for now but if trends show a deepening
moist column, this may be updated later.

Long term...
several nice days next week will be concluded with another cold
front that should be within the area by early Thursday.

Aviation...

Patchy areas of fog could bring MVFR visiblity and ceiling
restrictions to the terminals through around 14z. At kgpt, the fog
may be a bit thicker at times, and have a period of IFR visibilities
and LIFR ceilings around daybreak. After 14z, drier air aloft
should mix down resulting in VFR conditions for all locations. 32

Marine...

Increased northwest flow in the wake of a departing low pressure
system could bring some exercise caution winds of 15 to 20 knots to
the eastern waters today. The pressure gradient over the area
should decrease tongiht as a surface ridge settles over the Gulf
south. Winds are expected to fall below 10 knots and a veering of
the winds from the northeast to the southeast is expected Thursday
night into Friday as the ridge of high pressure shifts to the east.
A strong cold front should then sweep through the waters Friday
night shifting winds back to the northwest and increasing wind
speeds to near Small Craft Advisory levels late Friday night into
Saturday morning. A period of elevated winds of 15 to 20 knots from
the north should then persist through Sunday morning. Seas should
also increase to 4 to 6 feet during this period. High pressure
should become established off the eastern Seaboard by Monday and
Tuesday with sustained onshore flow around 15 knots expected across
the coastal waters. 32

&&

Preliminary point temps/pops...
mcb 76 53 81 56 / 10 0 0 0
btr 74 54 80 58 / 10 0 0 0
asd 76 55 79 57 / 10 0 0 0
msy 73 57 78 59 / 10 0 0 0
gpt 71 57 74 58 / 10 0 0 0
pql 73 55 77 56 / 10 0 0 0

&&

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

National Weather Service Glossary of Abbreviations