Just after I finished musing about how he helped us get a National Weather Service office in Huntsville again (since 2003), I saw that John Gordon, who has long moved on to being the Meteorologist in Charge of the Louisville, Kentucky NWS office, is retiring. And he wrote his last forecast discussion today. Which I'm reposting below. It is a joy to read through if you have the weather bug in you. And he has always been a great guy. So will also post a link to his most recent appearance on the Weatherbrains podcast, which he's appeared on many times. These are depressing times for meteorology, and he is one of those people who can remind you why you originally fell in love with the science. Even this text discussion makes that clear. The NWS is full of such people who aren't as well known to the general public but who as Alabama once sang, have a spirit you can't replace with no machine.
8:10 PM - Adding a link to "The Forgotten F-5" essay.
708
FXUS63 KLMK 272012
AFDLMK
Area Forecast Discussion
National Weather Service Louisville KY
312 PM EST Thu Feb 27 2025
.KEY MESSAGES...
* Isolated showers and low-topped thunderstorms possible in the
northeastern portions of the region, with gusty winds and small
hail possible.
* Breezy and mild Friday, then turning chilly for the weekend.
* Unsettled weather Tuesday and Tuesday night with a few strong
thunderstorms are possible Tuesday night.
&&
.SHORT TERM /THROUGH FRIDAY/...
Issued at 309 PM EST Thu Feb 27 2025
Sfc temperatures have warmed into the upper 50s and low 60s this
afternoon, with breezy westerly winds and increasing cu field. With
the upper shortwave trough swinging across the Ohio Valley, modest
sfc heating and cold mid-level temperatures have supported
steepening low/mid-level lapse rates across the area. GOES satellite
imagery shows cu agitation ongoing across northern Kentucky and
southwestern Ohio, where a pocket of MLCAPE has developed. SPC has
drawn a MRGL risk just to the northeast of the forecast area, which
is where better ML instability is expected through the rest of the
afternoon and early evening. With the General Thunder risk for our
area, we have a slight chance for a few gusty showers and storms,
with small hail or graupel possible given the cold mid-level temps
and low freezing level. PoP chances are constricted to our
northeastern quadrant of the CWA, and chances end by 00z this
evening.
Despite the PoP chances, breezy gradient winds will remain through
this afternoon as we mix down a 35-40kt LLJ. Wind gusts up to 30-35
mph will continue this afternoon, but do expect winds to relax by
this evening with the loss of heating.
For tonight, dry weather is expected with mostly clear skycover.
Winds will be much more relaxed, and will turn to a southerly
component by tomorrow morning. Temperatures overnight will fall into
the low to mid 30s.
For tomorrow, a second shortwave will track into the upper Ohio
Valley, and will be much more potent as a 50-55kt LLJ accompanies
the wave. Another day of steep lapse rates will support gusty sfc
winds, possibly reaching 40 mph. There was discussion for a Wind
Advisory for tomorrow, but the overall best confidence for
widespread gusty winds is just to our north. Will take this evening
to take another look at newer data, but definitely could see the
need for an advisory somewhere across the northern half of the CWA
tomorrow. Temps will reach the 60s due to the SW flow, and could
likely overachieve NBM temps.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Issued at 309 PM EST Thu Feb 27 2025
Well...I’ve written thousands of SFDs and AFDs over 30 + years, and
wrote them in the Air Force in Europe for 3 years, and this is my
very last AFD. Hard to believe, so here we go...
Friday night...
Winds will be dropping significantly after sunset. Cold front drops
through the Ohio Valley Friday night with only a wind shift and a
few clouds to show for itself. The FROPA should occur between 02 -
05z through the CWA and be from CRW to BNA to DFW by 12z Sat. Should
be some mid deck clouds but no ample forcing or moisture over the
CWA (well to the Northeast).
Saturday - Sunday...
CAA is the name of the game with a 1026 mb Canadian cP high moving
down into the Ohio Valley. Saturday will be a mix of sun and clouds
and Sunday more sunshine but temps will be in the 40-45 range
Saturday based on the Massie Rose 1000-850 mb technique and low
temps in 20-25 F range. Massie Rose yields highs Sunday even colder
than NBM with the upper 30s for zeniths.
Monday and Monday night...
Heights start rising in earnest by Monday morning as upper ridging
builds over the central Plains, but a closed upper low will track
eastward across the Red River Valley. The GFS is much more
aggressive on PoPS than the ECM as the feature washes out across the
Deep South on Monday night. My gut tells me we have too high of PoPs
for the initial wave Monday evening...however things really change
on Tuesday.
Tuesday...
A series of waves with decent isentropic ascent on Tuesday with 2
windows of precip. One is WAA with decent theta advection and
moisture transport during the day with some elevated instability.
The low level jet will be aiding in dew points climbing into the 40s
during the day and to around 50 by Tue evening.
Tuesday evening could be a significant problem with split flow and
distinct coupled jet with polar jet from Show Me State to Finger
Lakes of Western NY and Subtropical Jet from Lone State State to
Crimson State. A 543 dm low with a bit of a negative tilt in the
ARKLATX (and a warm front too) will be move from OK to Lake Erie. A
typical OH Valley High Shear event. The one positive for no severe
is there is deep moisture across soundings and no llvl instability
at this point. However, any increase in instability will be
problematic. However, could be a significant outbreak across the
ARKLATX, and SPC has them pegged.
Rainfall amounts look to be in the 1 to 2 inches, with the most
Tuesday night. Cold air will be filtering in behind the front and
would not be surprised to see snow light snow when the upper trough
comes through Wednesday night into Thursday.
Editors note...the Last discussion...
In 1993 I…
Started with one model (LFM) and now we have dozens of models and
even warn on forecast model (WoFS)
Started broadcasting Weather Radio with 8 track tapes and now NWR is
all automated
Started hand plotting Skew Ts and calculating all the indices and
now it’s all automated
Started working Korean War radars (FPS77, WSR-57) and now we have
Dual Pol Doppler Radars
Started with typewriters and fax machines, and now we have fast
computers.
In the 70s a nerdy kid in the Finger Lakes of Western NY, was
fascinated by lake effect snow (1977-78 had ALOT of snow). In the
1970s I was fascinated by Super Outbreak of 74, Eastern Airlines 66
microburst of 1975, Edmund Fitzgerald 1975, Big Thompson Flash Flood
of 1976, Johnstown flood of 1977, 2 major blizzards in 1978, and Cat
5 Hurricane David 1979.
In my 20 years at Louisville, we dealt with Hurricane Ike remnants
wind storm of 2008, the devastating Louisville flash flood of 2009,
the Massive ice storm of 2009, Henryville IN EF4 outbreak of 2012,
Dec 2021 Quad State Outbreak, and Feb 2025 Kentucky flooding event.
However, the signature event that stands out to me was the Super
Tuesday Feb 2008, with QLCS with many tornadoes at night, and long
track supercells and surveying for over a week!
Flew with the Air Force Hurricane Hunters WC-130 while working for
the NWS at JAN, SGF, OHX, HUN, and LMK. From 1993 to 2007, flew some
big hurricanes including Cat 5 Isabel and flew landfall mission on
Katrina in 2005.
Tried hard to move the needle in weather over 39 years including….
Changed from criteria based headlines to impact based headlines.
Wrote several papers including Winter Weather Checklist, Severe
Weather Checklist and The Forgotten F5 (a great read!!)
Lead national effort to raise severe thunderstorm criteria for hail
from 3/4” to 1” hail.
Lead national effort to change all NWS text products from upper case
lettering to mixed case and proper punctuation.
Issued first NWS flash flood emergency in Louisville in Aug 2009.
Began Meso AFDs across the WFOs...
Created the College Road Show and there have been 15 recruitment
events at Valparaiso, Purdue, Ball State, Indiana U, WKU and U of L.
Dozens of people are in NWS and weather enterprise because of the
college road show.
Started GIS across the Ohio Valley of the NWS, began aggressive
storm survey initiative, and GIS mapping showed the world where the
damage was etc…and saw our survey maps on TV.
Hope you’ve enjoyed some of my AFDs forecasting terms such as Massie-
Rose temperature technique, UPS Fog Technique, Garcia method, ACCAS,
FROPA, BINOVC, descriptive terms such as gelid, hyetal, torrid,
herculean, and always starting the AFD with Well….
Never forget some of the Gordon’isms
Play Offense
Own the Short Term
Pay it forward
It’s not what you think or feel, we must think impact based weather
Keeping service in weather!
After almost 40 years... Auf Wiedersehen
&&
.AVIATION /18Z TAFS THROUGH 00Z SATURDAY/...
Issued at 1228 PM EST Thu Feb 27 2025
With the cold front now departing to our east, sfc winds are now
primarily westerly flow this afternoon. With the primary cloud deck
shifting to the east, VFR flight categories are expected for the
forecast period. Winds are expected to pick up this afternoon, with
gusts up to 25-27kts possible. Some very isolated showers and storms
will be possible near LEX this afternoon, but expected coverage is
not enough to warrant mention in TAF at this time. Wind gusts will
relax by this evening with the sunset, leading to SKC and lighter
winds for the overnight. A stronger LLJ will approach the region
tomorrow, which will result in higher wind gusts possible tomorrow
afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.
&&
$$
SHORT TERM...CJP
LONG TERM...Gordon
AVIATION...CJP
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