Damaging Wind in Mississippi, June 24, 2022

Area Forecast Discussion
National Weather Service New Orleans LA
808 AM CDT Fri Jun 24 2022

.CLIMATE...
Let's look at some climate stats for New Orleans (MSY) and Baton
Rouge (BTR) to get a perspective of how unusual the recent heat
has been.

...MSY...

Official temperature records for MSY go back to 1946.

The high temperature of 99F yesterday, June 23, at New Orleans was
tied for the 5th warmest high temperature recorded in June. The all-
time record for June is 101F (June 24, 2009).

The average temperature over the past 7 days (June 17-23) was 88.1F.
This marks the hottest week in June on record (previous warmest week
in June was June 23-29, 2012 with an average temperature of 87.7F)
and the 17th warmest 7-day stretch of any time in the year. That
record could be broken again today and tomorrow.

Low temperatures over the past two weeks (June 10-23) have averaged
78.1F over the past 14 days. That’s the warmest two-week stretch in
June on record. The previous warmest was June 7-12 2010 (78.0F).

June 2022 is on pace for the warmest June on record based on a
monthly average temperature of 85.1F. The current warmest June on
record is 2011 with a monthly average temperature of 85.0F. It would
also be tied with August 2007 for the 15th warmest month on record
(impressive feat to compete with July and August records).

The temperature has reached at least 95 degrees each day for the
past 9 days. This is currently tied for the 5th longest stretch of
95-degree days on record. It’s also the first time MSY has recorded
this many consecutive 95-degree days in June. The latest forecast
supports this streak to extend to 11 straight days after the weekend
which would place it in a tie for the 3rd longest.

...BTR...

Official temperature records for BTR go back to 1894.

The average temperature so far this month is 83.9F. This would be on
pace to tie 1990 and 2011 for the warmest June on record at Baton
Rouge. It would also be tied for the 22nd warmest of any month on
record.

The temperature has reached or exceeded 95 degrees each day for the
past 12 days and 98 degrees for the past 6 days. This is currently
tied for the 10th and 8th longest stretches of 95- and 98-degree
days, respectively. It’s also the earliest time in the calendar year
Baton Rouge has recorded this many 95- and 98-degree days in a row.
The latest forecast supports this consecutive streak to extend to 15
95-degree days and eight 98-degree days which would place it in a
tie for the 8th and 6th longest such stretches on record,
respectively.

-JRK

&&

.PREV DISCUSSION... /issued 626 AM CDT Fri Jun 24 2022/

AVIATION (12Z TAF DISCUSSION)...

Expect VFR conditions for all area terminals this morning with
light to nearly calm surface winds and clear skies. Can't rule
out VCTS/brief TSRA for a few area terminals later this afternoon
and evening, with main impacts being brief gusty, erratic
downdraft winds and temporary flight category reductions due to
lower VIS in heavy rain. Will pinpoint/time terminals with
better chances in subsequent TAF cycles. Otherwise, expect VFR
conditions outside any showers or storms with all activity coming
to an end around sunset and staying calm tonight. KLG

PREV DISCUSSION... /issued 448 AM CDT Fri Jun 24 2022/

SHORT TERM (Today through Sunday Night)...

Well, it's hot. I could end the discussion there but we have a lot
more to talk about over the next few days. Starting with early
this morning with a quick synoptic overview, a broad, large-scale
ridging pattern continues to dominate a large majority of the US
as we reside right on the ESE periphery of the ridge center
roughly across north-central Texas. With heat being the
significant concern today and even bleeding into tomorrow, will
focus greatest discussion due to greatest impacts. Closely
identifying both ensemble/deterministic NBM trends from yesterday
to the latest guidance earlier yesterday evening revealed enough
confidence to keep a hotter bias going from previous forecasts,
aiming more towards the 75th to even 90th percentile in some
places. This brings ambient high temperatures today into the upper
90's to lower 100's areawide with several locations possibly
tying or surpassing daily records. Keeping the same highlights
issued yesterday in place for today with calculated maximum
apparent temperature values reaching excessive heat warning
generally for parishes along the I-10/12 corridor east to the
coastal MS counties. Societal impacts were considered as well in
these same areas in/around locations of urbanization as well as
morning lows in the upper 70's to lower 80's which will provide
little if any relief for the body to cool for those without access
to air condition or cooling centers. Outside of the dangerous
heat today, CAM guidance continues to confidently paint another
round of pop-up isolated showers and storms later this afternoon
thru the evening hours. Taking a closer look at forecast HRRR
soundings later today (comparing to previous days) illustrates a
persistently warm vertical thermal profile but with noticeably
less mid-level dry air compared to the past two days. This leads
to less forecast DCAPE values in the 1000-1100 J/kg range. Mean
storm motion will be light but likely towards the WSW to SW with
pulse-convection more confined to local small-scale boundary
interactions but overall, no major adjustments needed for PoP
coverage but as always, can't rule out a rogue strong storm or two
with sub-severe gusty winds the main risks (but hopefully may
bring temporary relief in the heat).

Going into the weekend on Saturday, same general story with
continued excessive heat concerns and likely advisories/potential
warnings to follow in subsequent forecast updates. Applied the
same warmer bias to guidance for highs which keeps us in just
about the same situation in regards to the heat. As mentioned in
the long-term discussion yesterday, we'll have a plume of deeper
tropospheric moisture over the southern Atlantic coast states
with PW's ranging 2.0-2.5" in some areas within a zone of slightly
lower surface pressure. This will continue to slowly translate
west with time, dragging deeper tropospheric moisture towards our
vicinity yielding greater daytime instability. Mean storm flow
continues out of the northeast meaning much of the same, if not
slightly more coverage expected on Saturday from NE to SW surging
thunderstorms. Didn't get too cute with PoPs keeping only a range
of 15-25% coverage for now, but feel this could be slightly
underdone given the steady airmass modification underway (perhaps
even deeper convection attempting to reach our eastern areas
late Saturday evening). But the influence of the aforementioned
strong ridge begins to pull back west, with this deeper plume of
moisture and subtle lift also continuing to drift west on Sunday,
where convective coverage becomes distinct enough to help lower
forecast MaxT/MaxAptT's just barely at Advisory criteria (if
that). Advertising around 30-60% PoP coverage again with
showers/storms possible at any point (likely starting as
widespread marine convection in the morning hours,
translating/increasing in coverage more inland throughout the
day). KLG

LONG TERM (Monday through Friday)...

Going into Monday and Tuesday, we remain confined within the same
zone of enhanced tropospheric moisture with a continuation of
enhanced coverage of showers and storms. With the ridge center
backing off some, this allows for a positive-tilt trough axis to
pull southeast across the Great Lakes into the northeastern US
along with an associated surface front drifting in from the
northwest which will aid in additional lift necessary for
thunderstorms, some of which could be locally heavy with flash
flooding the main risks. Similar to Sunday, convection will be
greatest over coastal/marine areas early translating inland more
throughout each day. Something of consideration glancing at GFS
model trends is what appears to be a developing cut-off upper-low
over right off the Atlantic coast of Florida, retrograding west
within mean easterly flow into the Gulf. Mid-level temperatures
would suggest this to be more cold-core aloft but eventual
location on where this feature ends up could lead to an
enhancement of convective coverage once more. Some indications are
for this low to drift northwest with time as 594dm ridging begins
to build over the southern Atlantic coast states allowing for a
weakness in heights over the northwestern Gulf, but otherwise not
seeing any strong indications of excessive heat returning next
week which is great news. KLG

MARINE...

High pressure across the region will continue to promote hot and
mostly dry conditions today, with some potential for coastal or
nearshore thunderstorms later this afternoon and evening. Rain and
storm coverage will increase later this weekend into early to
middle parts of the upcoming week as a weak easterly wave
approaches the area from the northeastern Gulf, drifting west with
time. Main impacts in any scattered strong to potentially severe
thunderstorms will be waterspouts, wind gusts >34 knots, dangerous
lightning and enhanced waves/seas but conditions will remain
mainly quiet outside of thunderstorm activity. KLG

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB 100  74  99  74 /  20  10  20  10
BTR 101  77 100  76 /  20  10  20  10
ASD 102  77 101  76 /  20  10  20  20
MSY 102  81 100  80 /  20  10  20  20
GPT 100  79  99  78 /  20  10  20  30
PQL 102  79 100  77 /  30  10  30  40

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory until 7 PM CDT this evening for LAZ034>037-039-046-
     056-059-065>071.

     Excessive Heat Warning until 7 PM CDT this evening for LAZ047-
     048-057-058-060-064-076>090.

     Heat Advisory until 10 AM CDT this morning for LAZ047-048-057-
     058-060-064-076>090.

GM...None.
MS...Heat Advisory until 7 PM CDT this evening for MSZ068>071-077.

     Excessive Heat Warning until 7 PM CDT this evening for
     MSZ080>082.

     Heat Advisory until 10 AM CDT this morning for MSZ080>082.

GM...None.
&&