Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/04/24
Area Forecast Discussion
National Weather Service Denver/Boulder CO
302 PM MST Sun Nov 3 2024
.KEY MESSAGES...
- A low pressure system will bring accumulating snow and cold
temperatures late today through midday Monday. Moderate snow
will fall across the higher terrain with impacts to travel,
especially during the Monday morning commute. 0.5-3" of snow is
forecast for the Denver metro with the Monday morning commute
seeing the brunt of the impacts.
- Ample uncertainty beyond Tuesday for a potential longer period
of unsettled weather across much of the region.
- Could we see two to three distinct waves of winter weather
Wednesday into the weekend, yes, but confidence is low on how
significant impacts will be at this time.
&&
.SHORT TERM /Through Monday/...
Issued at 213 PM MST Sun Nov 3 2024
Radar shows snow showers have developed over the mountains this
afternoon as a 500 mb trough approaches the region. Looking at
webcams, we can see that roads remain wet at this time, however,
this is expected to change as temperatures lower this evening and
snow levels drop below 5000`. Rain is expected for our foothills
and urban corridor this evening before transitioning to snow by
the early morning. Snowfall accumulations are expected to remain
mainly west of I-25 and south of I-76, with the highest
accumulations expected south of Denver where northerly surface
flow offers the best orographics. With the hi-res models showing
a steady uptick in QPF throughout the morning for areas including
the Indian Peaks and Mummy Range, we have decided to upgrade our
Winter Weather Advisory to a Winter Storm Warning for these
locations as heavy snow will be possible at times that may make
travel very difficult. Accumulations of more than a foot will be
possible in areas of heaviest snowfall. On top of the Winter
Weather Advisory already in place for our foothills locations
where an additional 3 to 6" of snowfall are expected overnight, we
have gone ahead and issued an additional Winter Weather Advisory
to include the Palmer Divide where up to 4" of snow are forecast
and expected to bring impacts to the Monday morning commute.
The snow is expected to taper off by late Monday morning as the
trough axis pushes east. Flow aloft will transition to
northwesterly by the evening, resulting in mostly clear skies and
dry conditions for the overnight hours.
&&
.LONG TERM /Monday night through Sunday/...
Issued at 213 PM MST Sun Nov 3 2024
...Continuing to see signs of a prolonged cold and snowy period
from Wednesday through Saturday...
Tuesday (Election Day) looks like the last high confidence
forecast day for a while, with Colorado in between storm systems.
The next major player in our forecast the rest of the week is a
strong short wave trough digging south out of western Canada on
Tuesday. The trough will be heavily influenced by a >150 kft jet
on the backside, which will drive it rapidly to the south. Lift
from the trough holds off until Wednesday, but there is
increasing west flow aloft, and with a little moisture working
in, light snow may begin as early as Tuesday morning in the
northern mountains, then spread to the rest of the mountains by
Tuesday afternoon and evening. Moisture is lacking and lapse rates
above ridge top are weak, so expect amounts on Tuesday to be on
the light side. It will also be windy across the Divide and east
slopes during the middle of the day with 40+ kts of cross barrier
flow and a weak inversion between 600-500 mb. There is a little
subsidence in the wake of the departing trough such that we expect
mountain wave enhanced winds to descend the east slopes a bit.
With that mountain wave enhancement, we have increased the winds
for the foothills but for now are keeping the higher winds out of
the adjacent plains into Tuesday afternoon. Gusts to 50 mph are
possible across the higher foothill locations. Downslope flow
across the plains should result in highs in the 50s, while ample
cloud cover and slowly cooling temperatures aloft mean the
mountain valleys should remain in the 30s.
With the "easy" day out of the way, attention turns to the overly
complicated forecast Wednesday through Saturday. The last long term
discussion used song lyrics to frame the discussion, so why not do
that again but this time with a hit song a year earlier than Bonnie
Raitt`s hit: "Things That Make You Go Hmmm" by C+C Music Factory.
We think we lost count with how many things are making us go hmmm
in the forecast from Wednesday through Saturday. We wish we could
say confidence is increasing with time, but that is simply not
the case. There are some broad brush aspects of how the cut off
trough could evolve, but the problem is that small changes in the
position and movement of the trough make massive differences in
the snow amounts and travel impacts across our area. The current
forecast has the 500 mb trough digging south on Wednesday to
somewhere from southeast Utah to western Colorado. It is extremely
positively tilted on Wednesday into Thursday, which will cause it
to cuts off from the main trough across southern Canada on
Thursday. Since it will be cut off from the polar jetstream, the
trough will slowly wobble eastward Thursday and Friday. Ensemble
guidance has the trough moving slowly from the Four Corners, then
across northern New Mexico, then ejecting it northeast into NE
Colorado or NW Kansas by early Saturday morning. There are well
established sweet spots in the location of the 500 mb and 700 mb
troughs for heavy snow across our area that are very much in play,
but given there is little agreement on the position/location
among models and among their ensemble members, confidence in how
this is actually going to play out is very low at this point.
Given the uncertainty, here is what we think could happen. A cold
front is expected to move across the plains of Colorado late Tuesday
into early Wednesday, and snow should develop associated with
increasing frontogenesis aloft Wednesday morning. Banded snowfall
could briefly be moderate and could impact the morning commute.
Plenty of synoptic lift and instability is expected to be in place
across the western half of Colorado Wednesday morning, especially
with a trough placement along the Utah/CO border. Thus, mountain
snow should also ramp up Wednesday morning, though upslope is very
weak in the mountains with flow turning southeast at ridge top as
the trough moves south into the Four Corners area. The QG lift goes
south with it, and sometime in the late evening mountain snow
showers may weaken or shut off, through some models keep it going
Thursday and Friday with the trough close enough to continue
providing a source of lift and instability. That`s definitely a
thing that makes us go hmmm, and something we`ll continue to
monitor. For now, if it does snow in the high country much of
Thursday and Friday, it will most likely light snow that adds up
to fairly impressive three day totals. With the trough sinking
south, the best snowfall would be favored along and south of I-70
in our mountains through Friday. Temperatures will remain below
freezing above 8 kft throughout the period, thus there is
potential for slick roads throughout the period as well, though
with lighter snow rates perhaps the impacts will be more limited
after Wednesday. For the plains, snow is likely to fall much of
Wednesday with plenty of lift and instability from the trough,
25kt of east upslope flow at 700 mb, and low-level northeast flow.
In that type of pattern the most snow would fall along the Palmer
Divide and along the foothills from Boulder County southward.
Slick roads are certainly possible for metro Denver/Boulder
Wednesday morning and again in the evening after sunset, with the
highest chances of slick roads for the foothills west of
Denver/Boulder and the Palmer Divide. Northern parts of the plains
may not see much snow Wednesday since they will be fighting the
downslope off the Cheyenne Ridge. Thursday and through half of
Friday, the near-surface flow should be northerly across the
plains and depending on the location of the trough, the best
forcing would be across southern Colorado. The best bet is for a
cool/cold, mostly cloudy day across most of the Plains, though
there could be accumulating snow south of I-76, especially along
and east of the Palmer Divide (another thing that makes you go
hmmm). Obviously if the trough is further north light snow could
fall much of the day Thursday into Friday across the I-25 urban
corridor, but for now the official forecast has the highest snow
chances across the Palmer Divide eastward to Kansas Thursday into
early Friday.
Easily the latest development in the forecast that makes you go hmmm
is Friday into Saturday if current model trends become reality. As
the trough moves east, it should encounter a boatload of Gulf of
Mexico moisture and a nice thermal gradient oriented SW to NE across
the High Plains which would force the trough to lift northeast with
a strengthening jet on the east side of the trough. The latent
heat release and temperature gradient could cause the trough to
rapidly deepen. A trough that intensifies that much and that
quickly will have an extensive TROWAL/wrap around region of
precip northwest of the bowling ball trough, and if the trough
moves from SE Colorado into NW Kansas, that wrap around intense
band of precip would be comprised of heavy snow across north
central Colorado. All models are now hinting that the cut off
trough could rapidly deepen and become negatively tilted later
Friday into Saturday, but the heavy snow and travel impacts are
tied to the position of the trough and the how much it
intensifies. It`s way to early to say with any confidence where
that might occur, and how strong it might become. Ensemble cluster
analysis, usually enlightening, isn`t much help yet with this
potential outcome. Every cluster has the cut off trough lifting
northeast, some have it deeper, some have it lifting faster, but
at this point all options are on the table from a heavy, high
impact snow on the high end, to cold with flurries on the low end,
and equally low chances of anything in between. Freedom Williams
could write a great rap about this forecast and add it as a verse
to his hit song. Much more to come as we get closer to the end of
the week.
&&
.AVIATION /18Z TAFS through 18Z Monday/...
Issued at 1042 AM MST Sun Nov 3 2024
An approaching winter storm is expected to impact the Denver area
TAF sites tonight through Monday morning. Rain is expected to
transition to snow around midnight tonight, with ceilings dropping
to MVFR by roughly the same time. Hi Res models are starting to
back off slightly on snowfall amounts at KDEN at this time, with a
trace to 1" forecasted for DEN and 1-3" for KBJC and KAPA. There
may be a period of .5"/hour of accumulations at the time of
heaviest snowfall, likely between the 7Z to 10Z time frame. Visibilities
may drop as low as 2 miles at KDEN, with a brief period of .5 to
1 mile vis possible at KBJC and KAPA. There is a chance that
ceilings drop to LIFR for a short time while visibilities are at
their lowest. Conditions are expected to improve quickly after
snowfall clears out, with MVFR expected to scatter out by the 19Z
to 20Z time range.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 11 AM MST Monday for COZ031.
Winter Storm Warning until 11 AM MST Monday for COZ033-034.
Winter Weather Advisory from 8 PM this evening to 11 AM MST
Monday for COZ035-036-041.
&&
$$
SHORT TERM...Bonner
LONG TERM...Schlatter
AVIATION...Bonner
Area Forecast Discussion
National Weather Service Burlington VT
939 PM EST Sun Nov 3 2024
.SYNOPSIS...
A warm front arriving on Monday will bring warming temperatures
through the middle of the week. Next chance for showers will
come mid week as a surface cold front crosses the area and
brings temperatures back down closer to normal.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 934 PM EST Sunday...Based on radar trends and latest 00z
data from the NAM 3KM/HRRR and RAP I have increased pops acrs
the SLV/northern NY after midnight and into Monday morning. This
also increases the potential for patchy freezing rain/mixed
precip during the Monday morning commute, especially the
northern SLV near KMSS where the crnt temps is 26F. Also, a few
slick spots possible in the deeper/protected valleys of the
northern Dacks. Greatest potential for freezing rain/mixed
precip is roughly from 09z-14z Monday. The qpf wl be light and
only a few hundredths of an inch, as lowest 5000 feet is fairly
dry and expecting some virga to occur as precip advects into dry
air from departing sfc high pres. A light glaze is possible in a
few locations acrs northern NY on Monday morning associated with
the very light wintry mixed precip. Rest of fcst in good shape.
Previous discussion below:
Surface and upper level ridging remain in place overnight,
keeping the region dry. Will have some high clouds in place and
moving into the area from the west ahead of an approaching warm
front. Temperatures will still drop pretty sharply despite the
high thin clouds, minimum temperatures will reach the 20s
areawide. Pretty dry air in place should help prevent any
showers from reaching the ground. On Monday our region will be
under warm air advection and southerly flow. Maximum
temperatures will reach the mid 40s to around 50 degrees. Winds
will increase in the afternoon and continue into the overnight
with tightened pressure gradient in place. Temperatures on
Monday night will not cool very much at all, maybe just a few
degrees. Chance for showers ill increase along our northern
border Monday afternoon into the overnight. Precipitation Monday
night will be light with two tenths of an inch or less
expected.
&&
.SHORT TERM /TUESDAY NIGHT/...
As of 354 PM EST Sunday...Biggest question marks for this
period may be related to cloud cover. A weak shortwave embedded
within the upper level flow will still be tracking over the area
while large scale lift occurs in the low levels with continued
warm air advection. This pattern typically leads to low clouds.
Shower chances will be highest over northern portions of our
region where cloudy skies are the surest bet into the morning
hours. Have leaned towards a blend of the latest deterministic
model guidance suggesting overcast skies through the first part
of the day, trending partly cloudy from south to north late as
drier air aloft helps scatter out some clouds. As such, high
temperatures across the board are trending a bit less warm.
However, the southerly flow will undoubtably help boost
temperatures even with limited sunshine. Temperatures should
reach into the 60s with with dew points returning into the 50s
by afternoon in most locations. Areas within the St. Lawrence
Valley are most likely to reach 70 degrees. Surprisingly, record
high temperatures are unlikely, in part due to a very warm
November 5th just two years ago. More interesting will be
overnight temperatures, as the combination of an unusually
strong 850 millibar southwesterly jet and rich moisture will
keep temperatures very mild Tuesday night. Temperatures will
remain well into the 60s overnight in the wide valleys with
mainly mid and upper 50s elsewhere.
With low pressure tracking so far to the northwest, frontal
forcing for precipitation will remain outside of the area until
possibly the very light night period as a plume of deeper
moisture arrives from the west. So precipitation chances ramp up
quickly after 2 AM, and become near 50-60% over most of
northern New York besides the Champlain Valley and far northern
Vermont/northern Greens with lower chances elsewhere. Chances of
rain will increase into Wednesday. Forecast soundings show
anomalous moisture but lack of instability with poor lapse rates
throughout the column of air. Jet dynamics are also unfavorable
for enhanced precipitation with a weakening upper level jet
streak still back to the west. So rainfall will be on the
lighter side, mainly under 0.1" through this period.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 354 PM EST Sunday...Wednesday will be a transition day
into a different weather pattern for the late week and weekend
as upper level flow shifts from southwesterly to northwesterly.
The potential for impactful wind on Wednesday has diminished
slightly with this forecast cycle, but gusty post-frontal winds
are expected, especially across the Adirondacks and
central/eastern Vermont where better mixing looks most favored
at this time. Dew points will fall greatly later Wednesday into
Thursday due to surface winds turning northwesterly. Fire
weather will be the main potential impact for this period, as
relative humidity will be trending lower and breezy westerly
winds will be possible, particularly on Friday when a pressure
gradient will increase with high pressure to our south and low
pressure passing to our north. Subtle frontal boundaries from
the north will pass through such that temperatures will trend
cooler through Saturday. Next real chance of rain doesn`t seem
to come until Sunday, but there is large uncertainty in timing
and storm track of the next system that could approach from the
west.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Through 00Z Tuesday...VFR conditions are expected to prevail
across all terminals for the next 24 hours. Despite light winds
and thin, high clouds early tonight, dry conditions are expected
to prevent much fog from occurring overnight. Later in the
night, increasing thicker high to mid level clouds will put a
cap on radiational cooling and any potential radiational fog
production. Winds will return out of the south/southeast
tomorrow morning at 5-10 knots, except at MSS, which will likely
have a more northeasterly wind direction. Winds will be
increasing at the surface and also aloft tomorrow afternoon,
resulting in southerly gusts 15-20 knots at BTV and LLWS
expected for SLK, MPV, EFK, and MSS 17Z-22Z onward.
Outlook...
Monday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Tuesday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Wednesday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Wednesday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Thursday: Mainly VFR, with local MVFR possible. NO SIG WX.
Thursday Night: VFR. Slight chance SHRA.
Friday: Mainly VFR, with local MVFR possible. NO SIG WX.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Neiles
NEAR TERM...Neiles/Taber
SHORT TERM...Kutikoff
LONG TERM...Kutikoff
AVIATION...Storm
Area Forecast Discussion
National Weather Service Dodge City KS
446 PM CST Sun Nov 3 2024
.KEY MESSAGES...
- Two major storm systems to impact the southwest Kansas region
through next Saturday.
- Storm #1 will provide large area of cold rain much of the day
Monday with widespread 1/2 to 1" rainfall likely.
- Storm #2 later in the week will also be a very wet storm
across much of the central and southern High Plains. Early
indications are widespread additional 1-2" of rainfall highly
possible based on latest ensemble 25th-75th percentile
output.
&&
.DISCUSSION...
Issued at 345 PM CST Sun Nov 3 2024
A very active weather pattern will continue through this forecast
period ending next weekend. Two Southwest Lows will move out across
the Great Plains, each of which bringing appreciable rainfall across
our southwest Kansas region.
This afternoon water vapor imagery and RAP analysis showed the
center of a deep mid tropospheric trough axis extending from Montana
south to eastern Arizona. The strongest upper level jet streak was
still on the western side of the trough axis, thus deepening and
closing off of a mid latitude cyclone has yet to occur and will
occur tonight as the base of the trough moves out across New Mexico.
By 18Z Monday, models have aligned fairly well with 500mb low
centered somewhere between Roswell and Clovis, NM with south to
north 500-700mb upstream of southwest Kansas, interacting with a low
level front which will be moving slowly south during the day Monday.
Abundant low level moisture will continue in the warm sector south
of the front from the eastern Texas Panhandle into Oklahoma, and
widespread rain will overspread southwest Kansas in the 12-15Z time
frame Monday.
The classic "comma head" of the maturing mid-latitude cyclone will
occur over southwest Kansas with fairly rapid occlusion occurring mid
to late day Monday as the mid level jet streak rounds the
southeastern portion of the cyclone. Frontogenesis centered around
700mb will increase from southwest to northeast from roughly Liberal
to Dodge City to Hays, becoming quasi-stationary through the
afternoon into the evening. This will likely be the axis of heaviest
rainfall amounts. 12z HREF has a large area of 25-75th percentile
rainfall amount range of 0.50 to 1.00". So, we have fairly high
confidence, both from forecaster experience of lows tracking to the
south of southwest Kansas like this, and from the model QPF fields
in a large portion of southwest Kansas seeing 1/2 to 1" of rain.
Some isolated peak amounts of 1.50 to 1.75" cannot be ruled out in
some portions of southwest Kansas, near the zone of strongest
frontogenesis, based on 90th percentile HREF fields.
This event will be all cold rain, although HREF does show some small
probSnow along the Colorado line, however given the spatial extent
of probSnow tied just to the Colorado line, we will keep all areas
liquid rainfall. Areas like Elkhart to Manter could see a couple wet
snow flakes mixed in during heavier precipitation. Most areas,
especially west of U283, will stay in the 40s during the afternoon
with the widespread rain and north surface winds. The storm will
pull away late in the evening Monday as it also weakens, so rainfall
rates will drop quite a bit in the 06-09Z time frame early Tuesday
morning. Tuesday will be quiet in between storm systems with light
wind and an MSLP pattern readjusting between the departure of
Monday`s storm and the approach of mid-late week storm.
By Tuesday Night and Wednesday, the next upper low will form across
southern Utah toward the Four Corners. This system will start off
more negatively tilt, which will allow the next round of colder air
and north winds to drive south ahead of the system. All the models
and ensemble system show the upper low anchoring and changing
orientation from positive tilt to neutral to eventually slight
negative tilt as the cyclone traverses the Southern Rockies. Low
level moisture will begin to push back northwest into the southern
High Plains (large area of 12+ degC 850mb dewpoint). The 850mb
response looks quite good on all models with strong southeasterly
winds at that level of 30 to 40 knots by late Thursday/Thursday
Night. This will manifest as a large area of showers and
thunderstorms just to the south of southwest Kansas with low level
moisture transport vectors pointed right toward southwest Kansas.
This is shaping up to be an even more meteorological impressive
storm for much of the southern and central High Plains,
including southwest Kansas, and it really will come down to
timing and the number of rounds of moderate to potentially heavy
rainfall. Right now, much of our area will likely see heaviest
rainfall from late Thursday Night into Friday Night.
Latest 100-member Grand Ensemble from 12Z this morning shows 25th-
75th percentile range of 1-2" for the event total with Storm #2 at
DDC over the period Thursday through early Saturday. There will be
much more concerning the late week to early weekend storm as we draw
closer to this event, so keep checking back for updates.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 441 PM CST Sun Nov 3 2024
Low clouds will once again envelop western Kansas overnight
with MVFR to IFR ceilings by sunrise tomorrow. Periods of
showers after 12Z tomorrow may lower visibilities to LIFR
conditions. Winds will initially be from a southerly direction,
shifting to the north with an increase in speed by sunrise
tomorrow. Wind gusts should remain below 25 knots late morning
into the afternoon.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Umscheid
AVIATION...Hovorka_42
Area Forecast Discussion
National Weather Service Goodland KS
620 PM MST Sun Nov 3 2024
.KEY MESSAGES...
- An isolated severe storm capable of producing quarter size
hail and/or wind gusts up to 60 mph remains possible over
portions of Gove, Sheridan, Graham and Norton counties through
11 pm CST this evening.
- Good chance (30%-70%) for rainfall on Monday.
- Rainfall/snowfall chances Tuesday night-Friday night.
&&
.SHORT TERM /THROUGH MONDAY/...
Issued at 253 PM MST Sun Nov 3 2024
This afternoon we are monitoring a cold front currently moving
over the Tri-State borders into Northwest Kansas. The dryline
moved over the Goodland ASOS about two hours ago which was a
little sooner than anticipated. This has led to a decrease in
confidence for severe weather over the western half of the area
and the current shape of the SPC Marginal risk area. We do have
some showers near the Kit Carson and Lincoln county border that
have struggled to mature and appear to be getting sheared out by
the ~60 kts of surface to 6 sm shear. SPC Mesoanalysis and RAP
guidance shows the best Surface- based CAPE (SBCAPE), ~1,000
J/kg, nosing northeast into the area from roughly Pueblo,
Colorado into Nebraska. As we move into the evening, instability
will be favored mainly along and east of Hwy 83. If that
corridor of instability can remain long enough for the cold
front to interact with it, we should be able to see some
isolated to scattered storms develop and move north-northeast.
The best window for severe weather is currently 4 PM to Midnight
(12 AM) MST/ 5 PM to 1 AM CST. The NAMnest has had the best
resolution so far with the activity coming off the Palmer
Divide, so the forecast leans more into that model. All hazards
remain possible for Northwest Kansas and extreme Southwest
Nebraska with concerns for up to ping pong ball sized hail, 60
mph damaging wind gusts, and a tornado or two can`t be ruled
out.
Rain will stick around behind the cold front into Monday evening as
it moves in from the south. Over the next 24 hours, it`s possible
some areas along our eastern edge could see up to 0.5" of rain. Some
light snow could mix in with the rain west of Highway 385 tonight.
However, little to no accumulation is expected given the warm soil
temperatures. Overnight lows will be in the 30s over the western
half of the area and in the lower 40s over the eastern half.
Temperatures on Monday will be a bit cooler than today with highs in
the 40s to lower 50s. Overnight lows will be in the 20s to lower
30s.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
Issued at 119 PM MST Sun Nov 3 2024
The long-term looks to be very unsettled with the potential for
some beneficial precipitation to occur.
Monday night we will see precipitation leaving the area to the
southeast as a trough extending into Mexico is pushed to the
northeast. Lows will cool into the upper 20s to lower 30s as the
precipitation ends. There could be a mix of rain and snow at
the tail end of the precipitation, too.
Tuesday will see a shortwave ridge move into the area, clearing
out the area and allowing us to warm into the upper 50s before
another trough impacts the area, starting Tuesday night,
starting an active pattern for the remainder of the period.
What will make this pattern so active is a trough descending
over the Great Basin, eventually becoming a closed low over the
Four Corners region on Thursday. This will merge the Sub-
Tropical and Polar jet streams over the Great Plains down to the
southeast CONUS. This positioning of the jet will allow a lee
low to form and likely linger around the Tri-State area.
Guidance is coming together to show the 850mb low will form over
southeastern CO on Wednesday, meander around Texas and Oklahoma
for most of Thursday, before moving north through KS. When the
low moves is a big question. The GFS has the low moving into
Nebraska by Friday mid-day and lingering around southern
Nebraska for the rest of the period. The ECMWF and CMC-NH show
the low moving north late Friday and into Saturday.
If the GFS is correct, we will likely see less precipitation
overall due to becoming dry slotted. This would clear out the
skies and allow us to warm up a bit more on Friday and Saturday,
likely into the 50s and maybe 60s.
If the ECMWF or CMC-NH is correct, we can expect more
precipitation falling in the CWA. This will be thanks to the low
wrapping around moisture into the area. This will also keep
temperatures notably cooler with persistent cloud cover and
northerly winds providing CAA until the low moves north.
For the precipitation, it is far too early to estimate exactly
how much locations will receive, but a couple of points are
sticking out. We will have our heaviest and best chances for
precipitation when the low is traversing around the CWA. Meaning
early Wednesday when the low forms and begins to move south,
and again when the low moves north into Nebraska. The time
inbetween will be stratiform rain that will generally be light.
We are also expecting mixed precipitation to occur. Rain is
expected in the east, where temperatures will be warmer with
snow becoming more likely in the western CWA. The line of where
snow will begin to mix in is impossible to pinpoint right now,
but it will likely waiver in between highways 385 and 83.
Temperatures Thursday morning are expected to be the coldest in
this period due to the fairly efficient CAA. Temperatures in
the far western CWA could drop into the lower 20s while the rest
of the CWA will cool to under 30F. Wind chills in the far west
could drop into the lower teens Thursday morning, too. We could
be spared the coolest temperatures if the CAA is a bit weaker as
the clouds would insulate us and the winds would keep the PBL
mixed.
A ridge will eventually build in from the southwestern CONUS
and push the low pressure system out of the area. This will
cease precipitation and allow temperatures to warm a few
degrees.
List of acronyms:
NBM - National Blend of Models
GFS - Global Forecast System
ECMWF - European Centre for Medium-range Weather Forecasts
CMC-NH - Canadian Meteorological Centre-Northern Hemisphere
CAA - Cold Air Advection
PBL - Planetary Boundary Layer
F - Fahrenheit
QPF - Quantitative Precipitation Forecast
MPH - Miles Per Hour
mb - Millibar
kts - Knots
km - Kilometer
CWA - County Warning Area
CONUS - CONtiguous United States
KS - Kansas
CO - Colorado
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 600 PM MST Sun Nov 3 2024
GLD: VFR conditions are anticipated to prevail overnight. MVFR
ceilings will develop late Monday morning (~16-19Z) and persist
for much of the afternoon.. before scattering out to VFR by
sunset. Northerly winds at 10-15 knots this evening will
increase to 20-30 knots after midnight (~06-08Z) and persist
through the duration of the TAF period.
MCK: VFR conditions are anticipated to prevail through the
majority of the TAF period. While a period of MVFR ceilings
(~2,500 ft AGL) is possible Monday afternoon, it`s possible that
ceilings may remain in low-VFR territory (~3000-4000 ft AGL).
Northerly winds at 10-15 knots this evening will increase to
15-25 knots by sunrise (~11-14Z) and persist through the
duration of the TAF period.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
SHORT TERM...KMK
LONG TERM...CA
AVIATION...Vincent
Area Forecast Discussion
National Weather Service Indianapolis IN
922 PM EST Sun Nov 3 2024
.KEY MESSAGES...
- Warmer than normal temperatures expected through next weekend
- Chances for rain through Monday, focused over the northwest
half of central Indiana
- Near record warmth Monday-Tuesday ahead of possibly more
widespread showers Tuesday/Tuesday night
&&
.FORECAST UPDATE...
Issued at 921 PM EST Sun Nov 3 2024
- Mild and Cloudy overnight.
- Chances for light rain west.
Surface analysis this evening shows strong high pressure in place
over New England. Deep low pressure was found across the Central
Plains states. This resulted in Indiana being caught between the two
systems, with a warm and mild SE-S flow in place. Water vapor
imagery continues to show a large plume of moisture stretching
across the southern and central Plains stretching northeast to the
Great Lakes. Radar mosaics show abundant precipitation beneath this
plume, mainly over MO/AR/E OK and E KS. Dew points across the area
remained rather high, in the upper 40s to middle 50s.
Overnight the strong surface high to our east looks to continue to
block quick eastward progress of the moisture. The highly amplified
upper pattern shows a similar slow progression east. This will keep
the continued mild and southerly flow in place across Central
Indiana through the night. The previously mentioned area of rain
showers are expected to push northeast within the flow, arriving in
the far western parts of central Indiana during the overnight hours.
HRRR depicts this well, showing arrival within the Wabash valley
near 09Z, with continued progression northeast. This keeps most the
remainder of Central dry overnight. A stray sprinkle cannot be ruled
out during the overnight hours. Thus will keep some pops included
late overnight across the west, with minimal to no pops across the
east, but perhaps a sprinkle mention.
Regarding temps, warm southerly flow looks to remain in place. This
along with cloud cover will make for a mild night. Temperatures
should remain rather steady state or just fall slightly overnight.
Look for lows in the upper 50s to lower 60s.
&&
.SHORT TERM (This evening through Monday)...
Issued at 239 PM EST Sun Nov 3 2024
Rest of This Afternoon...
Mid level clouds covered all but far eastern sections of central
Indiana early this afternoon. radar shows some light rain/sprinkles
across eastern Illinois, moving into far northwestern portions of
the forecast area.
The initial round of isentropic lift that was producing the light
rain early this afternoon will continue to push northeast. Will keep
some chance PoPs northwest with some slight chance PoPs or a
sprinkles mention farther southwest. Any rain that falls will help
moisten the lower layer of the atmosphere.
Warm temperatures in the 60s and lower 70s will continue.
Tonight...
Weaker isentropic lift will continue this evening, but lift will
increase overnight as the low level jet increases. The jet will also
bring in moisture. Southerly surface winds will bring in additional
moisture for the low levels.
The flow aloft will continue to allow warm and moist flow across
Indiana and the TAF sites. Mainly mid cloud ceilings are expected,
resulting in VFR Conditions. A moderate LLJ, over 40 knts pushing
through the Wabash Valley, will pass across the area tonight.
This could result in some LLWS due to speed.
Some MVFR ceilings are possible on Monday as a wave of forcing
arrives during the late morning hours producing showers and some
lower cigs.
As the forcing departs by mid Monday afternoon, showers will end,
but VFR Cigs will remain.
Believe there will be enough forcing and moisture to go likely
category or higher PoPs by late tonight in the far northwest, with
lower PoPs to the southwest where forcing will be weaker.
Southerly winds plus cloud cover will keep temperatures unseasonably
warm for lows, with low temperatures around 60 to the lower 60s.
Monday...
Similar conditions will continue on Monday. 850mb winds will be
around 50kt. Decent moisture will be around thanks to continued
southerly flow.
Isentropic lift will continue, but the approach of the left exit
region of an upper jet will bring additional forcing, especially to
the northwest forecast area.
Will once again go with likely or higher category PoPs across
portions of the northwest, with lower PoPs to the southwest
(farthest from the forcing).
With a warm start, temperatures may reach the lower to perhaps
middle 70s for highs. If clouds are thicker and/or rain more
widespread, readings will top out cooler. Even in that scenario
readings will be well above normal.
&&
.LONG TERM (Monday night through Sunday)...
Issued at 239 PM EST Sun Nov 3 2024
Monday Night through Tuesday Night...
An impressive 1036mb high over the southern Appalachian Mountains
will tighten the pressure gradient Sunday night through Monday as a
short wave pushes in from the west. This will create blustery
conditions with strong WAA into the Midwest and Ohio Valley regions.
Dry antecedent surface air will inhibit moisture transport some, but
this WAA should result in widespread cloud cover Monday night, with
isolated light showers possible. The combination of widespread
cloud cover and strong southerly WAA will lead to well above normal
temperatures Monday night. In fact, the overnight low Monday night
is likely to remain higher than the average high for early November!
We are also on Max-Min record watch with the monthly record
maximum low of 63F and the forecast low on Monday night of 63F.
Ensemble members are trending towards a weakening low pressure
system as this shortwave reaches the Ohio Valley on Tuesday. This is
likely due to the wave remaining positively tilted in the WAA
regime. The weakening of the low will limit moisture
transport/convergence on Tuesday along a passing cold front,
reducing overall QPF expectations for central Indiana. This will
also keep the bulk of cold air aloft to the west, creating weak mid
level lapse rates and lessening thunder probabilities. Still, a band
of weak to moderate showers are expected to pass through central
Indiana midday Tuesday through Tuesday evening; current QPF
expectations are between 0.15" and 0.40" with this frontal passage
Wednesday through Saturday...
Despite the cold front label from Tuesday, the air mass behind this
system will remain mild due to continued shortwave development over
the Plains, causing a the lack of connection with the cold air over
the Canadian Rockies`. This will keep 850mb temperatures in the upper
single digits(C), resulting in above normal highs through the
extended. These aforementioned shortwaves shouldn`t have much of an
impact to central Indiana, as high pressure will remain strong just
to our S/E. Any impact from these shortwaves will likely be in the
form of periods of increased cloud cover and isolated showers.
&&
.AVIATION (00Z TAF Issuance)...
Issued at 623 PM EST Sun Nov 3 2024
Impacts:
- Gusty winds through the period.
- Non-convective low level wind shear tonight, mainly at BMG
- Chance for MVFR ceilings at KLAF on Monday
Discussion:
Southwest flow aloft will continue to allow warm and moist flow
across Indiana and the TAF sites. Mainly mid cloud ceilings are
expected, resulting in VFR Conditions. A moderate LLJ, over 40 knts
pushing through the Wabash Valley, will pass across the area
tonight. This could result in some LLWS due to speed.
Some MVFR ceilings are possible on Monday as a wave of forcing
arrives during the late morning hours producing showers and some
lower cigs.
As the forcing departs by mid Monday afternoon, showers will end,
but VFR Cigs will remain.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Puma
SHORT TERM...50
LONG TERM...Updike
AVIATION...Puma
Area Forecast Discussion
National Weather Service Jacksonville FL
827 PM EST Sun Nov 3 2024
...New UPDATE...
.UPDATE...
Issued at 820 PM EST Sun Nov 3 2024
For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf
Strong high pres continues over New England area with a long fetch
of easterly low level flow over the western Atlantic toward our
area. Slight troughing in the low levels near the coast and fairly
high moisture up through about 8500 ft is helping to maintain a
chance of showers for mainly the eastern zones and the marine
waters. We note from 00z Sounding that PWAT is now up to about
1.5 inches compared to near 1 inch at 12z. Expect that the shower
activity will be more confined to about the first 2 tiers of coastal
counties later tonight as the airmass stabilizes further inland.
Still, some sprinkles could spread further inland later tonight,
mainly in southeast GA where higher moisture will be located.
Boundary layer winds appear to be a bit too strong for much of any
patchy fog for inland areas. Min temps will be held to the 60s
most areas except for lower 70s along the coast due to the breezy
onshore flow. Main updates were to trend POPs toward latest radar
trends and follow some of the enhanced moisture fields from the
guidance and latest HRRR during the day on Monday. Otherwise, no
other significant changes planned at this time.
&&
.NEAR TERM...(through Tonight)...
High pressure ridging continues today and into tonight continuing
onshore flow and low level moisture over the area. Scattered
showers will continue to make their way inland from the coast
mainly over northeast Florida this afternoon, shifting north into
Southeast Georgia overnight. Today highs will be in the upper 70s
to low 80s region wide. Overnight temperatures will be in the low
60s over southeast Georgia and mid to upper 60s over Northeast
Florida staying slightly warmer along the coast.
&&
.SHORT TERM...(Monday through Tuesday night)...
Breezy onshore flow persists through Tuesday with a strong,
dominant surface high and supporting blocking ridge aloft
situated northeast of the region. Moisture will be lacking a bit
Monday as another inverted coastal trough develops. The lack of
moisture will challenge shower development over the coastal waters
and lead to mainly dry conditions.
By Tuesday, transport flow will start to veer southeasterly,
sending a plume of rich tropical moisture into the region. That
moisture intrusion will gradually grow instability Tuesday
afternoon, mainly across north-central FL, where an isolated
thunderstorm could develop. Temperatures will be boosted by the
flow and will challenge daily record maximum temperature records
(CLIMATE section below), especially Tuesday with highs pushing
into the middle 80s!
&&
.LONG TERM...(Wednesday through Saturday)...
Stubborn upper ridge will begin to break down and flatten as a
shortwave rides overtop of it Wednesday into Thursday. The rate
that this occurs will dictate the main weather story this week -
the potential tropical system that is currently brewing in the
southwestern Caribbean. That system will be steered into the
southeastern Gulf of Mexico Wednesday and slow down and may stall
Wednesday night into Thursday as steering flow weakens. Though
uncertainty exists in the direction of this system Thursday and
Friday, the main threat for the local area will be the potential
for heavy rainfall. Latest ensemble guidance indicates, the
heaviest rainfall and potential for flooding will focus northwest
of the area along a stalled frontal boundary. Temperatures will
stay above normal this period as rain chances push above climo
with the tropical airmass lifting across the region.
&&
.AVIATION...
(00Z TAFS)
Issued at 650 PM EST Sun Nov 3 2024
Over the next few hours, low broken clouds expected to affect most
of the TAF sites with IFR expected at times for CRG, VQQ, and
SSI, and low-end MVFR cigs for SGJ, JAX, and VQQ. Appears that GNV
and SGJ have better odds of VFR cigs. Isolated to scattered
showers expected tonight but will most likely for the coastal
areas north of SGJ. The IFR conditions from CRG to SSI may linger
past midnight and may need to amend for SSI later tonight where
IFR clouds could continue. However, based on HREF and HRRR the IFR
cigs appear to shift further inland after 06z into the inland
sections of southeast GA. Monday, another chance of isolated
showers but looks few and far between to include a VCSH for all
the TAFs. There may be an MVFR cig around Monday morning 11z- to
14z but overall probabilities appear low enough to indicate only
FEW-SCT stratocu deck for now. Sfc winds will be relaxing from the
northeast to about 5-10 kt tonight and then becoming more
easterly about 10-14 kt and gusty on Monday.
&&
.MARINE...
Issued at 213 PM EST Sun Nov 3 2024
High pressure ridging continues over the area into the beginning
of the week as a strong high pressure system over the Great Lakes
slowly moves offshore of coastal New England Monday. This will
help continue coastal toughing over adjacent waters producing
daily coastal showers. A Small Craft Advisory has been issued for
strong East-northeasterly winds and higher seas over the Southeast
Georgia waters today and continues into early part of the week.
High pressure moves further into the Atlantic by mid- week as a
potential Tropical System develops in the Caribbean Sea and moves
northward into the southern Gulf of Mexico.
Rip Currents: High rip current risk for all area beaches through
Tuesday.
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 79 63 84 / 10 20 10 10
SSI 67 78 70 81 / 30 30 10 10
JAX 66 83 68 85 / 30 10 10 10
SGJ 70 81 71 83 / 30 10 10 20
GNV 65 84 66 86 / 20 10 10 10
OCF 65 84 67 86 / 0 20 10 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk until 4 AM EST Monday for FLZ124-125-133-
138.
GA...High Rip Current Risk until 4 AM EST Monday for GAZ154-166.
AM...Small Craft Advisory until 2 PM EST Wednesday for AMZ450-470-472-
474.
Small Craft Advisory from 5 AM Monday to 2 PM EST Wednesday for
AMZ452-454.
&&
$$
Area Forecast Discussion
National Weather Service New Orleans LA
523 PM CST Sun Nov 3 2024
...NEW AVIATION...
.SHORT TERM...
(This evening through Monday night)
Issued at 306 PM CST Sun Nov 3 2024
This afternoon, recent radar/obs trends indicate some very
shallow/light shower activity across coastal SE LA underneath a
persistent onshore, moist return flow regime. Taking a step back
and looking at the state of the troposphere using the 12Z KLIX
RAOB and HRRR sounding trends illustrate a moistening low-levels
from the LCL around 3kft AGL to the base of a subsidence inversion
at around 8.5kft AGL, which given warm afternoon temperatures
helping to develop a well-mixed PBL, has provided a slither of
positive bouyancy in this aforementioned layer. SPC
Mesoanalysis/sfc wind obs indicate subtle surface confluence
extending in an axis from well offshore south of Mobile Bay, NW to
Plaquemines Parish also influencing in the support for these
shallow showers. NBM PPI is not picking up on this activity
(perhaps, best being the HRRR initializing it somewhat) so did add
in manually to 14 PoP for drizzle mention to 15 PoP for iso
showers across mainly coastal areas into tonight. Just one of
those moist return flow situations where a passing rogue
shower/drizzle can be squeezed out at any time, but tried to
pinpoint greater chances in the forecast.
Otherwise, forecast hodographs indicate a slight increase in
depth/curvature in the low-levels starting this afternoon,
highlighting a steady uptick in WAA pattern building across the
region. This gusty region in the vertical being at the top of the
boundary layer will support downward flux transport of breezy
winds this afternoon/evening, and regardless of decoupling, will
keep winds "elevated" enough tonight to reduce surface fog
production/maintenance. This gives scientific reasoning behind the
NBM`s drop in low visibility probabilities, however may still see
low stratus in locations like we typically see in this type of
warm pattern. Also, did catch on going back on verification to
notice we`ve been a tad too cool with overnight lows. With this
warm/moist flow intensifying and remaining parked over the area,
didn`t hesitate to hedge closer to the 75th percentile for
overnight lows keeping them quite warm, likely breaking some
record warm lows (BTR specifically has a record warm low of 69
Monday, set in 1959, 1973 and 1988 with a forecast low of 74. MSY
record warm low of 71 on Monday, set in 1975 with a forecast low
of 74). Just something to watch.
Starting out the new work week tomorrow fairly similar to today.
Warm again with highs flirting with records in some locations yet
again. Breezy at times in the afternoon, and can`t rule out an
isolated rogue shower or two (did manually introduce ~15% PoP in
the afternoon for most areas) but generally speaking, primarily a
dry day with partly to mostly cloudy skies.
Did want to briefly touch on the coastal flooding situation.
Guidance this afternoon started to highlight a bit more of a
concern for impacts mainly during/around high tide cycles coming
up. More particularly, the Monday night into early Tuesday morning
tide cycle being the peak with Waveland`s current NAEFS-Based
forecast touching ~4-4.2ft MLLW / 2.4-2.6ft MHHW in the 90th
percentile. Went ahead an extended the advisory for coastal areas
from originally ending 6AM Monday to now 6AM Tuesday, but did
introduce a Coastal Flood Watch for south and east-facing
shorelines from Hancock, south to SE LA coastal areas 00Z TUE -
12Z TUE to account for this impactful cycle potentially needing a
warning. Will let subsequent shifts/updates take a closer look at
the guidance to decide to upgrade to warning or revert to
advisory, but wanted to get the messaging out for now all due to
increase SE flow/fetch in the forecast. KLG
&&
.LONG TERM...
(Tuesday through Saturday night)
Issued at 306 PM CST Sun Nov 3 2024
Now to spend some time in the long range... we`ll see how fast I
get a headache by the end of it. Starting out with an overview,
persistent, deep 588dm H5 ridging remains anchored over the SE
Atlantic coastline, staying strong and not wanting to budge much.
Meanwhile, a positive-tilt longwave trough axis over the central
US, responsible for the active weather out that direction will
quickly deamplify and weaken racing northeast around the periphery
of the ridge. Surface reflection highlights a weakening surface
low ejecting up across the Midwest into the Great Lakes region,
with trailing cold front progressing slowly east across the MS
valley region. The combination of the strong ridge in place and
weakening upper-level support will slow the front to our
north/west to a crawl, likely stopping before sliding through our
area before turning back north as a warm front (or what would be
left of it) into Wednesday. So locally, staying warm with the
moist return flow parked in place, still a chance of an isolated
shower or two but mainly dry.
Then there`s the tropics. We`re already starting to see
slow/steady development with a tropical wave in the south-central
Caribbean. NHC has now brought this system up to a Potential
Tropical Cyclone #18 as this system will likely continue to
develop. Will go ahead and say, for the short-term, confidence is
higher with ensemble spread honing in on the movement through the
next 60-84 hours continuing to drift northeast, north, then
northwest towards the Isle of Youth/NW tip of Cuba in a generally
favorable environment. Briefly looking at intensify forecasts
shows a pretty large swath of solutions, with the possibility of
either slow /steady development, or quickly growing much stronger
as what some of the dynamical hurricane models show. For now,
NHC`s track/intensity reaching hurricane strength by the time it
reaches the NW Caribbean impacting far western Cuba. But as the
system continues northwest, could start to encounter a degree of
southwesterly shear and even dry air meaning some weakening is
possible as it gets more into the Gulf mid-week. Small additional
tidbit about the wind shear/dry air: Don`t discount that. Looking
at water vapor right now shows the intense depth of tropospheric
dry air across the southern periphery of the ridge from the mid-
atlantic, west to the GOMEX and will continue to pump west as the
system punches through it to the northwest with time. If the wind
shear can take more of a hold of it, tilts the system more to the
east and allows the dry air to work into it, could really make a
difference. This time of the year, with baroclinic systems diving
much farther south hosts all sorts of challenges in and variables
to monitor, It`s practically an atmospheric balance game. Ridge
strength, position, system intensity, position, speed,
degree/location of shear and dry air and how it`ll interact with
the system all are in question this far out. Not going to
pick/choose guidance, not going to side one way or the other but
wanted to emphasize the NHC`s forecast seems very spot on given a
collective understanding of all the variables mentioned, but could
still change and bears close watching. I know a hurricane in the
Gulf in early November was probably not on a lot of peoples bingo
card for the 2024 Hurricane Season, but goes to show the need to
stay vigilant, and ready/prepared at any point during hurricane
season. As we get into around mid-week, more will become clearer
so check back and we`ll do our job to pass along the latest
information. KLG
&&
.AVIATION...
(00Z TAFS)
Issued at 517 PM CST Sun Nov 3 2024
No low VIS/fog tonight as low level flow remains elevated.
However, there will be some low stratus possible with brief
reductions to MVFR or perhaps IFR, especially BTR, HDC, and MCB.
Otherwise, VFR conditions can be anticipated. Southeast winds
will increase again on Monday with some gusts up to 25 to 30kts
not out of the question, especially coastal terminals. (Frye)
&&
.MARINE...
Issued at 306 PM CST Sun Nov 3 2024
Persistent onshore southeasterly flow will continue tonight into
early/middle portions of this upcoming week. Winds on average
around 15-20 knots can be expected, with occasional gusts to 25
for all Gulf waters and portions of the Sounds have led to Small
Craft Advisories that remain in effect. Increasing/intensifying
fetch across the Gulf will also lead to a response in waves/seas
increasing tonight into Monday and Tuesday. However, gradient
flow is expected to relax more around mid-week, with a temporary
reduction in winds and waves/seas. Next focus will be on the
potential for a tropical system in the southern and central Gulf
late week. For now, confidence remains low on specifics to impacts
to the local marine waters. For the latest information, visit
www.nhc.noaa.gov. KLG
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 69 83 68 83 / 10 20 10 40
BTR 74 88 73 87 / 10 10 20 40
ASD 70 84 69 85 / 20 20 10 20
MSY 74 85 73 85 / 10 20 10 20
GPT 71 82 71 83 / 20 20 10 20
PQL 71 86 70 87 / 20 20 10 20
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 69 83 68 83 / 10 20 10 40
BTR 74 88 73 87 / 10 10 20 40
ASD 70 84 69 85 / 20 20 10 20
MSY 74 85 73 85 / 10 20 10 20
GPT 71 82 71 83 / 20 20 10 20
PQL 71 86 70 87 / 20 20 10 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Coastal Flood Advisory until 6 AM CST Tuesday for LAZ058-060-077-
080-082-084-086>088.
Coastal Flood Advisory until 6 PM CST Monday for LAZ066>070-076-
078.
Coastal Flood Watch from Monday evening through late Monday
night for LAZ066>070-076-078.
GM...Small Craft Advisory from 9 PM this evening to 6 PM CST Monday
for GMZ536-538-550-552-555-557-572-575-577.
Small Craft Advisory until 6 PM CST Monday for GMZ570.
MS...Coastal Flood Advisory until 6 AM CST Tuesday for MSZ087-088.
Coastal Flood Advisory until 6 PM CST Monday for MSZ086.
Coastal Flood Watch from Monday evening through late Monday
night for MSZ086.
GM...Small Craft Advisory from 9 PM this evening to 6 PM CST Monday
for GMZ538-550-552-555-557-572-575-577.
&&
$$
SHORT TERM...KLG
LONG TERM....KLG
AVIATION...RDF
MARINE...KLG
Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
536 PM CST Sun Nov 3 2024
...New AVIATION...
.SYNOPSIS...
Issued at 330 PM CST Sun Nov 3 2024
Warm and windy conditions will persist tonight and Monday ahead
of a cold front. A slow-moving cold front will bring showers and a
few thunderstorms to the Mid-South Tuesday and Wednesday.
Unsettled weather will continue through late week as the front
remains over the region.
&&
.DISCUSSION...
(This evening through next Saturday)
Issued at 330 PM CST Sun Nov 3 2024
It`s a warm and windy day across the Mid-South. We have seen
several wind gusts over 35 mph as a 40 knot 925mb jet remains
overhead. Temperatures are in the upper 70s to around 80 degrees
across the entire area. The latest KNQA radar sweep reveals a
large swath of showers moving south to north across portions of
eastern Arkansas. Hi-res models failed to capture this activity
this far east, but trends suggest that it will taper off by this
evening as upper level heights build back in. Thereafter, mainly
dry and windy conditions will persist over the next 24 hours.
The large trough, currently over the Intermountain West, will
deepen over the next 24 hours and a strong low level jet will move
overhead. 925mb winds will strengthen to 50 knots over the Lower
Mississippi Valley tomorrow. This will result in moderately windy
conditions across at least the western half of the forecast area.
The strongest winds appear to be over northeast Arkansas and the
Missouri Bootheel, but could expand east of the Mississippi River.
Current NBM guidance is underperforming wrt to winds, so opted to
go with NBM 90 and a higher gust multiplication factor. Sustained
winds of 20 mph will be prevalent across the majority of the area
with 25 mph or greater mainly over northeast Arkansas and the
Missouri Bootheel. A wind advisory is in effect from 9AM to 7PM
tomorrow for the aforementioned area.
A cold front will move into the region late Monday night and
slowly traverse the area through Wednesday. The highest rainfall
totals will occur mainly on Tuesday with 1 to 1.5 inches possible.
The front is expected to stall across the region through late
week, as the main trough dampens and lifts northeast of the
region. Deep southwesterly flow will setup across the region on
Thursday in response to another deepening trough over the Four
Corners Region. The stalled front will back north of the region
on Thursday. Chances for near-record high temperatures will occur
on both Thursday and Friday.
Newly introduced Potential Tropical Cyclone Eighteen, that is
currently in the western Caribbean Sea, will move northeast
through the Gulf of Mexico over the next week or so. This
system`s track will need to be closely monitored, as it has the
potential to interact with a mid-latitude cyclone in the Lower
Mississippi Valley next weekend. Both Ensemble and Deterministic
guidance suggest that tropical moisture will interact with a
frontal boundary over the Mid-South next weekend. Significant
rainfall could occur over portions of the Mid-South as PWATs climb
above 2 inches. Stay tuned.
AC3
&&
.AVIATION...
(00Z TAFS)
Issued at 537 PM CST Sun Nov 3 2024
Raw HRRR and GFS/LAMP guidance suggest current trend of limited gusts
will persist through about 03Z. LLWS remains marginal across the
Midsouth overnight, peaking at 09Z with about 20 degrees of
veering through lowest 2kft. Isolated -SHRA will primarily affect
JBR, but should present relatively limited impact.
Primary aviation weather impact for Monday will remain gusty
southerly surface winds, peaking 15Z-18Z with the deepening low
level mixed layer.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Wind Advisory from 9 AM to 7 PM CST Monday for ARZ009-018-026-
028.
MO...Wind Advisory from 9 AM to 7 PM CST Monday for MOZ113-115.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...AC3
AVIATION...PWB
Area Forecast Discussion
National Weather Service Pocatello ID
724 PM MST Sun Nov 3 2024
.UPDATE...
HRRR shows patchy fog and low stratus developing in the Magic
Valley later tonight. This is an area where skies are mostly clear
and likely to see fog/stratus. If it develops it will likely
expand towards Shoshone, Craters and towards the Coldwater area.
13
&&
.PREV DISCUSSION... /issued 112 PM MST Sun Nov 3 2024/
SHORT TERM...Afternoon visible satellite imagery shows gradually
clearing skies across the region as the weather system that
brought clouds and snow to the area shifts to the east. The break
in clouds and precip will be short-lived as our next system will
come during the second half of the day Monday but for now, things
are relatively quiet. We could still see an isolated snow shower
this afternoon across the higher terrain of the central mountains
or eastern highlands but even these will be hard to come by beyond
sunset. Skies will clear decently overnight allowing for temps to
drop into the teens 20s throughout the region, single digits
around Island Park and Stanley.
By mid to late afternoon tomorrow, clouds will begin to increase
ahead of our next weather system as an upper level trough again digs
into the area with some enhanced waves of vorticity moving through
the base of the trough sparking another period of snow for the
region. Snow will primarily be focused across the higher terrain,
especially the eastern highlands and areas that perform well in NW
upslope regimes. Overall totals have trended downward somewhat and
look generally sub-advisory but some light accumulations can
certainly be expected. Does look like the lower valleys won`t see
much with this feature but some snow showers, maybe a light dusting,
will be possible but shouldn`t be anything too problematic. As this
feature moves in, winds will increase especially late Monday and
into Tuesday AM so we could have some blowing/drifting issues in
some of our usual higher elevation trouble spots but winds aren`t
that strong so these concerns are likely more isolated. After this
system, we should have some more sunshine and drier weather to
contend with at least for a few days. More on that below. McKaughan
LONG TERM...Tuesday through next Sunday.
The upper trough and associated cold front will shift southward on
Tuesday through Idaho before high pressure returns for the majority
of the extended timeframe and keeps dry conditions in the forecast
Wednesday through next Saturday. This system will be quick-moving
with modest snow totals, which have trended slightly lower since the
last forecast package. Snow accumulation through late Tuesday will
be 2 to 7 inches above 6,000 feet with localized peaks seeing closer
to 9 inches and a Trace to an inch below 6,000 feet. While many of
our mountain passes further west are looking to only receive a
couple inches of snow, Raynolds Pass and Targhee Pass will see
closer to 4 inches with Emigration and Pine Creek Passes forecast to
receive 5 to 6 inches. Our low elevations below 5,000 feet will see
a rain/snow mix. Winds ahead of and along the front will be windy,
with sustained winds generally 25 to 35 mph and gusts 35 to 50 mph.
Considering the timing and widespread coverage of these winds, the
potential for blowing/drifting snow and localized reductions in
visibility will be elevated. All of Southeast Idaho will observe
much colder temperatures during the period, with both high and low
temperatures running 10 to 20 degrees below climatological norms at
times. Overnight temperatures will take a big hit Tuesday night
behind the front, with clear skies allowing overnight lows to drop
into the teens and single digits CWA-wide. Temperatures will
decrease overall through around mid-week before high pressure
returns and helps to warm temperatures back into the 40s and within
several degrees of "normal" across much of Southeast Idaho by
Saturday. After that, ensembles feature another Pacific trough
moving onshore late Saturday into Sunday. Cropp
AVIATION...Skies continue to clear across much of the area and
VFR should prevail at all terminals except KDIJ into the first
half of the day tomorrow. KDIJ is still dealing with lingering
clouds and light snow showers that can lead to some MVFR/IFR
reductions. Will have to monitor the potential for some overnight
stratus from KBYI up the Snake Plain to KPIH and KIDA but for now,
the forecast doesn`t show this. Winds will be light for the next
24 hours as well but will pickup late Monday and into Tuesday AM
as our next system moves through. McKaughan
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Springfield MO
541 PM CST Sun Nov 3 2024
.KEY MESSAGES...
- Multiple rounds of showers and thunderstorms will continue
through Tuesday. Confidence is high in several inches of rain,
with widespread totals of at least 2-5" by the end of the
event, with localized amounts up to 6-9" confined to narrow
corridors. The heaviest rainfall axis is currently located
along and south of a Branson to Salem line.
- There is a Slight (level 2 of 5) Excessive Rainfall Risk on
through Monday. A Flood Watch is in effect for portions of SE
KS and portions of far S MO from 6pm Sunday through 6am
Tuesday due to multiple rounds of rainfall.
- Sunday Night Severe Outlook: Slight severe risk (level 2 of 5)
for Springfield and points southwest tonight as thunderstorms
move out of Oklahoma and Arkansas. Damaging winds up to 60mph
and a line embedded tornado are the main threats.
- Monday Afternoon/Evening Severe Outlook: Enhanced (level 3 of
5) Risk for the far SW corner of Missouri and a Slight (level
2 of 5) Risk for most of the rest of the Missouri Ozarks.
Damaging winds would be the primary threat with the line of
storms, though there will also be the potential for a few
embedded tornadoes.
&&
.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 145 PM CST Sun Nov 3 2024
Current Conditions and Synoptic Pattern: A highly amplified
shortwave trough was located across the Rockies with deep
southwest flow aloft across the region. Low level moisture
continues to stream into the area with the 12z KSGF sounding
measuring 1.35in of PW which is near the max for early November.
A low level front has lifted north of the area earlier this
morning with low 60 dewpoints common across the area. This front
then stretches west into low pressure across western Nebraska. A
dryline was located across west Texas. A batch of showers and
thunderstorms moved into the area this morning however it
continues to move east, affecting areas along and east of
Highway 65. Cloud cover was thick across the area which has
kept temps down into the low 60s. This is keeping the
instability to a minimum with the latest RAP showing less than
250j/kg of ML and MU CAPE.
This afternoon and evening: Additional energy is moving into
western Oklahoma and has already initiated showers and
thunderstorms across Oklahoma in a more unstable environment
(ML CAPE over 1000j/kg). This activity will likely begin to
enter southwest Missouri during the 4-8pm timeframe. The lack
of instability should keep these storms subsevere with just a
few lightning strikes and moderate rainfall rates.
Overnight: As we head into the late evening and overnight hours
there are indications that instability could increase slightly
as the low level jet intensifies again. The highest chances of
seeing this instability increase will be to the southwest of
Springfield (Joplin/Pineville). However the latest 12z HREF
does not increase much instability overnight. This has
implications on our severe and rainfall threats overnight. A
corridor of severe storms looks to develop across central and
eastern Oklahoma this evening and then push northeast into
western Arkansas. These storms will attempt to then move
northeast into southwest Missouri. 0-6km shear of 40-50kts is
plenty for organized storms however the instability seems to be
the limiting factor for a more widespread severe event. However
we will be monitoring the instability levels, especially on our
00z sounding this evening. If storms can maintain severity into
the area then damaging winds up to 60mph and a tornado will be
the primary concerns. Highest severe chances are southwest of
our area.
The other concern for the overnight hours is the potential for
training thunderstorms given the extremely high moisture content
and continued low level jet feeding convection. Latest 12z
guidance suggests that this corridor could set up just to the
southeast of I-44. This does follow the southward qpf trend
over the last 12-18 hours. Where this corridor sets up will
experience rainfall rates of 1-2 inches per hour. The latest
HREF (LPMM) guidance shows potential for 2-5 inches of rainfall
in this corridor with the overnight round of rainfall with a
50-70% chance of 4 inches or more along and south of a
Gainesville to Salem line. However since this is a convective
rainfall event, any deviation north or south with the storms could
have serious implications on these amounts. The current Flood
Watch remains in effect and no changes planned for the area or
time.
Monday through Monday Night: The upper trough will continue
pushing east during the day and while there will be morning
rain, we do think that there will be some periods of dry time
during the day. This will have big implications on instability.
Surface low pressure will continue to develop across Oklahoma
and move into southeast Kansas by the afternoon with the dryline
along with it. Of concern is the latest HREF guidance
indicating 1000j/kg of CAPE developing across the area during
the afternoon and evening. This would occur if we could get some
dry time/peaks of sunshine otherwise CAMS could be too
aggressive with instability. By late afternoon and evening
guidance breaks out scattered to numerous showers and storms
along the front from eastern Kansas into eastern Oklahoma.
Forecast soundings show strong wind fields aloft with 0-6km
shear around 60kts and 0-3km shear of 50kts. Therefore
instability will be critical to the severity of thunderstorms.
If instability is high enough (ML CAPE 500-1000j/kg) then line
segments will develop with damaging winds up to 60mph and QLCS
tornadoes. We will need to monitor this threat closely with the
enhanced risk just southwest of Springfield. This would likely
be during the mid evening and overnight hours as the line sweeps
through the area.
Additional rainfall with this round looks to be in the 1-2 inch
range. When combined with previous rainfall, LPMM data suggests
a widespread 2-5 inch storm total with a corridor of 6-9 inches
of rainfall. While many areas are in drought, drought conditions
are not as severe in the eastern CWA. This is also the most
flood prone area of our CWA therefore we will need to closely
monitor river and creek levels. Latest HEFS guidance indicates
potential for several creeks and rivers to rise into Action and
or Minor flood stage however this will be highly dependent on
that heavy rainfall axis. A few river Flood Watches have been
issued already.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 145 PM CST Sun Nov 3 2024
The trough will be pushing through the area during the day
therefore expecting a decrease in clouds/rain during the day.
Ensembles suggest that the southwest flow pattern will not go
away with a quick return by Wednesday as another disturbance
moves into the Rockies. Ensembles begin to diverge by Thursday
as the guidance is split on the trough closing off and slowing
down or ejecting faster east. Currently the majority of guidance
is much slower therefore rain chances are currently low for
Wednesday and Thursday (10-30%) and then increasing Friday into
Saturday (30-50%). The speed of this trough will greatly affect
precip chances late next week. Temps look to remain around
average (highs in the 60s).
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 536 PM CST Sun Nov 3 2024
Rounds of showers and thunderstorms will continue to push
through the area tonight into Monday night. Storms may be strong
tonight and could be severe on Monday afternoon into Monday
night. Gusty winds and strong wind fields aloft will continue
as well.
&&
.CLIMATE...
Issued at 145 PM CDT Sun Nov 3 2024
Record High Minimum Temperatures:
November 3:
KSGF: 63/1994
November 4:
KSGF: 59/1994
Record Precipitation:
November 3:
KJLN: 2.05/1974
November 4:
KSGF: 2.32/1994
KJLN: 2.16/1994
KVIH: 1.91/1994
KUNO: 2.20/1994
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
KS...Flood Watch through late Monday night for KSZ073-097-101.
MO...Flood Watch through late Monday night for MOZ066-077-078-082-
083-088>098-101>106.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Burchfield
AVIATION...Titus
CLIMATE...Burchfield