Special Weather Statement, NWS New Orleans, LA

AREA FORECAST DISCUSSION
National Weather Service New Orleans LA
421 AM CST Wed Feb 10 2021

.SHORT TERM (Today through Friday)...
Current upper level analysis shows zonal flow across the eastern
half the country with a trough south of California and high pressure
draped across Florida and portions of the Gulf of Mexico. This setup
has been and will continue to produce muggy and warm conditions
locally. Low/mid clouds seem to be winning out over fog at the
moment but still have some opportunity before sunrise. Thus will be
keeping dense fog advisory in effect until mid morning. If nothing
develops by 7am, will be canceling early. The fcst temps are a
degree or so above NBM based on the typical(and observed yesterday)
trend of NBM missing airmass moderation rate. Expect another day
with highs 10 to 15 degrees above normal. Ample moisture already in
place combined with a weak stalled front draped across central LA
will be all thats needed to spark convection today. Model soundings
shows mild/modest CAPE means at the least will have thunderstorms
develop. Wetbulb zero of around 10kft means there's some possibility
that a few storms produce hail. Thinking SPS type storms mostly with
the low probability of needing a severe warning.

Moving into Thursday, the trough currently located southwest of CA
will track eastward into southern Texas while a more broad trough in
Canada expands south. This will cause the front in central Louisiana
to slowly push south into the CWA. Expect nearly 100% coverage with
a mix of showers and thunderstorms. Some areas could see an inch or
2 of rainfall throughout the day. This will be the last day of above
normal temps for awhile. Cooler air pushing in behind the front will
keep highs on Friday down to low 50s and low 60s. Lingering showers
will likely persist through probably early afternoon before finally
shifting south and east.

MEFFER
&&

.LONG TERM (Saturday through Tuesday)...
This portion of the forecast continues to be the most challenging
for a couple reasons. Those being frozen precip potential and
terrible model consistency. In nearly 15 years of forecasting, I
can't remember a time when guidance changed so drastically. The
culprit is models trying to resolve weaker shortwaves with broad
troughing with bitter cold situated to the north. Don't feel like
there's much question that it will precip over the CWA at some point
this weekend and into early next week. It's just a matter of whether
the lower portions of the atmosphere will support anything frozen.
Looking at 1000-500mb thicknesses as well as model soundings, the
answer is no. If you look at the setup broadly, possibly, as
repeated reinforcements of cold air with rain potential will give you
some chance. But, if you look at the medium range models' forecast
track of the upper low early next week, its quite far north for what
typically produces frozen precip here. For those reasons, have
pulled SN/ZR from the forecast for now.

MEFFER
&&

.AVIATION...
LIFR conditions will be possible at most area airports during the
early morning hours Wednesday due to dense fog. This fog will be 1/4
SM or less over land areas and will likely persist through the mid-
morning hours. By lunchtime, IFR/MVFR conditions will dominate due
to low ceilings and the possibility of isolated vicinity showers
near the airports. Fog will be possible again overnight Wednesday
night, which could cause lower visibilities and potentially IFR/LIFR
conditions to return. MSW

MEFFER
&&

.MARINE...
Generally onshore flow will persist through much of the week. This
will bring increasing dewpoints which will likely result in areas of
fog over the cooler nearshore waters as early as tonight and persist
for a few days. Late week through this weekend is still a bit
uncertain. Blend of guidance suggests once the first front moves
through Thursday night, a series of 2 to 3 reinforcements of that
offshore flow will occur over the weekend and into early next week.

MEFFER
&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  72  60  68  44 /  50  50 100  90
BTR  77  63  73  48 /  50  40 100  90
ASD  77  60  74  53 /  50  20  90  80
MSY  73  63  75  55 /  40  20  90  80
GPT  68  60  72  56 /  50  20  90  80
PQL  71  60  73  55 /  50  10  80  80

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Dense Fog Advisory until 9 AM CST this morning for LAZ040-
     046>050-056>070-072.

GM...Dense Fog Advisory until 9 AM CST this morning for GMZ530-532-
     534-536-538-550-552-555-557-570-572-575-577.

MS...Dense Fog Advisory until 9 AM CST this morning for MSZ080>082.

GM...Dense Fog Advisory until 9 AM CST this morning for GMZ532-534-
     536-538-550-552-555-557-570-572-575-577.

&&

Special Weather Statement
National Weather Service New Orleans LA
917 AM CST Wed Feb 10 2021

MSZ081-082-101600-
Jackson-Harrison-
917 AM CST Wed Feb 10 2021

...A STRONG THUNDERSTORM WILL AFFECT EAST CENTRAL HARRISON AND
SOUTHWESTERN JACKSON COUNTIES...

At 917 AM CST, a strong thunderstorm was located over D'iberville, or
over St. Martin, moving east at 15 mph.

Pea size hail is possible with this storm.

Locations impacted include...
Biloxi, Ocean Springs, St. Martin, Gautier, D'iberville, Latimer,
Gulf Hills, Gulf Park Estates, Vancleave and Hickory Hills.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3034 8870 3037 8885 3038 8885 3037 8881
      3038 8878 3043 8885 3043 8893 3042 8894
      3040 8888 3039 8888 3039 8899 3041 8899
      3042 8896 3051 8890 3053 8866 3036 8866
TIME...MOT...LOC 1517Z 259DEG 15KT 3043 8890

KLG