Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/25/24
Area Forecast Discussion
National Weather Service Birmingham AL
744 PM CST Wed Jan 24 2024
...New SHORT TERM, AVIATION...
.SHORT TERM...
(Tonight through Thursday)
Issued at 708 PM CST WED JAN 24 2024
Enhanced, southerly low level wind fields will keep the column
moisture content near record highs into Thursday. The 00z BMX Raob
measured 1.72 inch precipitable water values. Based on radar data
and observations, it appears that areas near and west of I-59
received 2-3 inches of rain since midnight. A few locations had
some minor flood issues with the heavy rainfall, but no flash
flooding has been reported. Rivers will also be on the rise the
next several days due to the rain. Moisture convergence in the
lower levels should remain in the vicinity of I-59 during the
overnight hours. This axis will then move north and then south yet
again as a short wave trough moving overhead Thursday afternoon.
The highest flood threat may be north, but will leave the watch
going as is for now. Another 2 inches of rain is possible through
Thursday with locally higher amounts. As mentioned in previous
forecast, a near saturated atmosphere remains in place on
Thursday. Shear values as the short wave moves overhead will
remain supportive of thunderstorms, but we must realize some
instability. That will remain the question as we head into the
next 30 hours. We may need to introduce stronger storms if the
instability can develop in this environment. Otherwise,
unseasonably mild.
75
Previous short-term discussion:
(This afternoon through Thursday)
Issued at 1247 PM CST WED JAN 24 2024
The forecast area remains between deep troughing over New Mexico
and Broad ridging to our southeast over the Bahamas. A swift
southwest flow remains entrenched overhead in the mid-levels while
mid-level impulses continue to move northeast over the area. Rich
low-level moisture is in place with deep moisture content aloft
with the 24.12z BMX sounding yielding a precipitable water value
of 1.34 inches. Additionally, strong low-level moisture transport
across much of Mississippi into Northwest Alabama was noted due to
RAP mesoanalysis depictions of a 50 kt LLJ across portions of
South-Central into Eastern Mississippi. A few areas of lower
pressure were analyzed on the surface map across the Lower
Mississippi River Valley Region while high pressure was well to
our northeast just off shore of the Northeastern Seaboard.
Tonight.
The embedded shortwave will round the trough base, resulting in
the trough taking on a sharper neutral tilt after midnight as it
over over Eastern Oklahoma and Texas. The surface cold front will
advance eastward, extending from the Mid-South Region south into
Southwest Louisiana toward daybreak.
Expect continued shower activity overnight with a few isolated
thunderstorms possible with the better potential south and west
where the better instability and support will be positioned.
Continued rainfall overnight will result in soils becoming
saturated and water runoff increasing. Areas that experience
continued moderate to heavy rain may experience localized flash
flooding, especially in urban and low-lying areas.
Winds will be from the south at 4-8 mph. Low temperatures will
range from the upper 50s north to the mid 60s far southeast.
Thursday.
The mid-level trough opens into a more potent shortwave that
takes on a negative tilt over much of Arkansas through the day.
The enhanced support aloft will favor the development of surface
low pressure across the Mid-South Region that will quickly lift
northeast into the Ohio River Valley Region by early evening.
Expect chances for showers to remain high along with an increase
in thunderstorm activity with better chances to the west
initially, then moving further east into the area through the day.
If sufficient instability materializes, sufficient dynamics will
be available to support some more organized thunderstorm activity,
which could support a small risk for damaging winds and perhaps a
brief tornado. This risk is conditional depending on how much
low-level buoyancy can materialize through warm advection as skies
will be cloudy over much of the area.
Moderate to heavy rainfall on top of saturated soils will
continue to pose a risk for flash flooding, especially in
urbanized, low- lying and poor drainage areas. Water rises on
creeks and streams will be noticable as we continue to see rain
showers across the area for another day. Area river capacities
still have some room for added discharge but some of the more
narrow channels will see some noticable rises with time as well.
Winds will be from the south, becoming southwest by late
afternoon with wind speeds from 6-12 mph. High temperatures will
range from the mid 60s far north to the low 70s far south.
05
&&
.LONG TERM...
(Thursday night through next Tuesday)
Issued at 219 PM CST WED JAN 24 2024
A zone of high PWATs will remain across Central Alabama Thursday
night through Friday night. Scattered to numerous showers and a
few thunderstorms expected Thursday night, but not expecting
any significant rainfall totals or strong storms. The models are
in agreement in developing a meso-low off the Louisiana coast
Friday morning and tracking it northeast across southeast Alabama
Friday afternoon or evening. The track of the the meso-low will
play a factor in the potential for severe storms across the
southeast counties. The farther north of the track of the low, the
greater the potential for severe storms. Given the uncertainty of
the track and small area affected, will hold off for now on
mentioning any severe storms. However, the speed and intensity of
the low will certainly produce some impactful weather.
There will likely be a lull in the rain Friday evening as another
upstream storm system gathers strength. A closed upper low will
move into the Southern Plains states Friday evening. Convection
will develop rapidly along the MS River Friday evening and
advance quickly eastward as the upper low takes on a negative
tilt. Abnormally high PWAT values and surface dewpoints in the 60s
will already be present across central Alabama Saturday morning.
With the main convective line moving through Alabama during peak
heating period, the ingredients are available for the development
of severe storms, mainly across east Alabama Saturday afternoon
and evening. SPC will issue a Day3 convective outlook later
tonight which will include Saturday, and will let the overnight
shift fine tune the threat potential on Saturday.
The rain will finally shift east of Alabama Saturday evening with
colder and drier conditions Sunday through Tuesday.
58/rose
&&
.AVIATION...
(00Z TAFS)
Issued at 708 PM CST WED JAN 24 2024
Flight restrictions are anticipated the next 24 hours at all
terminals. There will be a few areas of convection moving over
central Alabama this period. Variable ceilings with widespread
showers and few thunderstorms to start. The main area of
convection will stay in the vicinity of the northern
terminals overnight, but all areas could experience showers or a
storm. The southerly flow and nearly saturated conditions will
allow ceilings to drop to IFR/LIFR before 12z. Rain chances remain
high the entire time. Vis will be impacted the most during heavy
rainfall. Some patchy fog may also be around, but a lesser
restriction than above mentioned. Winds will generally be
southerly around 10kts with some gusts to near 20kts. Winds just
aloft also increase overnight. At this time, too much convection
will be in the neighborhood to mention any LLWS.
75
&&
.FIRE WEATHER...
A wet and unsettled weather pattern is expected across the area
through the end of the week. Rain opportunities for most periods
are expected for the entire forecast area. Rainfall could be
locally heavy at times, with chances for thunderstorms. Minimum
RH values will be well above critical thresholds each day.
20ft winds will be southeast at 5-7 mph tonight, becoming
southerly 7-9 mph on Thursday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 58 69 57 68 / 100 100 90 60
Anniston 60 69 60 70 / 100 100 90 70
Birmingham 59 68 60 67 / 100 100 80 60
Tuscaloosa 60 71 57 69 / 100 100 70 50
Calera 60 69 60 68 / 100 100 80 70
Auburn 61 68 62 69 / 80 100 80 90
Montgomery 63 72 62 72 / 90 100 70 90
Troy 65 72 64 72 / 70 100 70 90
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Thursday evening for the following counties:
Autauga-Bibb-Blount-Calhoun-Chambers-Cherokee-Chilton-Clay-
Cleburne-Coosa-Dallas-Elmore-Etowah-Fayette-Greene-Hale-
Jefferson-Lamar-Lee-Lowndes-Macon-Marengo-Marion-Montgomery-
Perry-Pickens-Randolph-Shelby-St. Clair-Sumter-Talladega-
Tallapoosa-Tuscaloosa-Walker-Winston.
&&
$$
SHORT TERM...75
LONG TERM....58/rose
AVIATION...75
Area Forecast Discussion
National Weather Service Cheyenne WY
427 PM MST Wed Jan 24 2024
.KEY MESSAGES...
- Mountain snow returns Thursday with the potential for 3 to 6
inches of accumulation in the high country through Friday.
- Light snow possible Thursday night for areas west of the
Laramie Range. Total snowfall accumulations below one inch.
&&
.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 153 PM MST Wed Jan 24 2024
Current radar returns show some light scattered showers just south
of the Wyoming/Colorado border. The HRRR suggests more showers
developing over the western zones of the CWA later this afternoon
and spreading eastward into the Nebraska panhandle by this evening.
As a result, did bump up PoPs to give slight chance wording as the
HRRR is one of the only Hi-Res models to show any precipitation. Any
showers that do develop will be light and short-lived, so expect a
quiet overnight.
A fairly weak upper-level trough will push into Wyoming tomorrow,
bringing some light mountain snow and perhaps some flakes to
southeast Wyoming. The bulk of the moisture with this trough will be
well to the south with the low pressure center in northern New
Mexico. There will still be good low to mid-level moisture for areas
west of the Laramie Range combined with good frontal lift, which
could lead to some light snow falling Thursday night. Accumulations
for the plains will be on the light side, with total snowfall
amounts under one inch likely. Snowfall amounts will be higher in
the mountains as the duration of snow will be longer, likely lasting
through much of the day Thursday and through Friday. Decent
orographics will also be present at the onset of the system which
will help with the snowfall amounts. By the end of the day Friday,
the Sierra Madre and Snowy Ranges could see between 3 and 6 inches
of accumulation.
Besides snow chances, this trough will bring cooler temperatures to
the CWA on Friday. Temperatures behind this weak front will be
about 5 to 10 degrees cooler compared to Thursday. However, high
temperatures will still be hovering near average for this time
of year. Expect a chilly Friday night as low temperatures fall
into teens and low 20s.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Issued at 153 PM MST Wed Jan 24 2024
Continuing to look at a warming trend with dry weather throughout
the long term period into next week. Deterministic models begin to
build an upper level ridge over the Intermountain-West this weekend.
By Sunday, 700mb temps will climb to near 0C across much of the CWA
per the latest GFS with GEFS support for 700mb temps to approach 5C
for the middle of next week. This will help temperatures reach the
50s starting Sunday afternoon becoming more widespread into early
next week, mainly east of I-25 into the NE Panhandle. Latest NAEFS
and EC guidance continues to show 700mb temps reaching above
climatological 90th percentile values for late January for Tuesday
and Wednesday of next week. Decided to nudge up afternoon
temperatures as the deterministic NBM for most sites sits on the low
end of the distribution, likely due to our recently cold
temperatures resulting in a harsher bias correction. Latest cluster
analysis shows strong ensemble support for the ridge to center over
the central CONUS and persist through next week that could support a
prolonged drier and warmer period before a potential pattern change
late next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 420 PM MST Wed Jan 24 2024
Issues with the 00Z TAFs will be possibility of MVFR conditions
at KRWL this evening. Latest HRRR guidance showing low
conditions near KRWL for a couple hours with showers in the
area. These showers quickly dissipate this evening with VFR
conditions returning. Think low stratus and fog in the Panhandle
will stay east as downsloping westerly winds become more common.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...SF
LONG TERM...MB
AVIATION...GCC
Area Forecast Discussion
National Weather Service Grand Rapids MI
1037 PM EST Wed Jan 24 2024
.KEY MESSAGES...
- Dense fog persisting into Thursday
- Risk for heavier rain Thursday night
- Rising rivers and localized minor flooding possible
&&
.UPDATE...
Issued at 1036 PM EST Wed Jan 24 2024
We will stay the course on the going forecast for dense fog
tonight. Plenty of boundary layer moisture with the melting
snowpack and rainfall from today. Consensus of short term model
guidance continues to show widespread dense fog reforming
tonight. This guidance worked well last night and feel it
reasonable again tonight. The rain has acted to dissipate the
fog a bit and slow the onset of dense fog, but now that the rain
is coming to an end expect a slow deterioration in visibilities.
We do have a bit more wind around 1,000 feet tonight as compared
to last night, but feel the downward trend in visibilities will
occur. So, the Dense Fog Advisory will remain unchanged.
&&
.DISCUSSION...
Issued at 230 PM EST Wed Jan 24 2024
- Dense fog persisting into Thursday
Several sites were showing visibilities around a quarter mile,
even for the middle part of the afternoon. As we go through the
night and temperatures drop off a few degrees, we should see the
thicker fog expanding. The 18z HRRR was showing the denser fog
increasing in coverage overnight. We will therefore maintain the
Dense Fog Advisory. Overnight lows for northeast parts of the
CWA may fall to near freezing which could lead to a few slick
spots or patchy freezing drizzle. Overall we are not expecting
there to be much drizzle around by the time temperatures fall
to near freezing so we are not planning on issuing any headlines
for that risk. With lows near freezing, patchy ice is a
possibility on untreated surfaces once again later
tonight/tomorrow morning.
- Risk for heavier rain Thursday night
There has been a trend towards bringing this next batch of rain
in a little later. Thus it is looking like Thursday night into
early Friday will be the main period for the risk of heavier
rain. The Canadian RDPS model continues to feature the most
rain with values potentially making a run at 1.5 inches. This
model has been an outlier with the amounts so we are leaning
away from its solution. The ECMWF is closer to an inch while
the GFS is around three quarters of an inch. The 18z HRRR is
closer to a blend of the ECMWF and GFS. Based on all this, its
looking like amounts will likely end up in the half inch to an
inch of rain range. Highest amounts are likely to be over the
southern 2/3rds of the CWA. This will be a dynamic system
featuring strong upward vertical motion as the system takes on a
negative tilt as shown at 500 mb. Close monitoring will be
needed going forward given the range of amounts shown by the
models.
- Rising rivers and localized minor flooding possible
Discussion: As of Wednesday afternoon, we`re currently in the 2nd
round of a 3 round warm and rainy weather pattern. The snowpack
across most of our area continues to act like a sponge and absorb
the ongoing rain, rather than sending water moving toward the rivers
yet. This will change this evening as the snow should reach
saturation and begin releasing water. This will eventually lead to
river rises, but it`s the 3rd round of rain expected tomorrow
(Thursday) night that will be what really gets the water moving
toward the rivers.
Thursday night (into Friday morning) should be super sloppy as snow
melts and more rain falls. The water will reach the smaller
streams/tributaries first, and our focus is on the smaller rivers
generally around the Lansing area (Looking Glass, Maple River,
Sycamore Creed, and Red Cedar) for the highest chance to exceed
bankfull and possibly approach minor flood levels by early this
weekend. Eventually this water flows into the main Grand River
itself, which will see large rises, but no significant flooding is
expected.
The other factor to consider is the ice that remains on some of the
larger rivers - specifically parts of the Grand River near Comstock
Park. While the ice remains in place at this time, it`s already
showing signs of losing strength. So while we do expect this ice to
eventually start shifting and moving around, the risk for breakup
ice jams remains fairly low simply because the ice doesn`t appear
that it will have enough strength to cause much of a problem.
However, if you live near an ice-covered river - and especially a
spot with a history of ice jams - now`s a perfect time to pay extra
attention and make a plan for what you`d do if the water started
rising.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 730 PM EST Wed Jan 24 2024
Another 24 hours of poor aviation conditions are expected.
Ceilings will be below 400 feet for the next 24 hours for the
most part. We should trend visibilities once again tonight
towards 1/4SM. So, widespread VLIFR conditions are anticipated
late tonight and Thursday morning. Rain will begin to push in
during the late afternoon from the south Thursday afternoon,
with the bulk of the rain arriving after 00z. Winds will be
below 10 knots through the 24 hour forecast period of 00z to
00z. Direction should become easterly on Thursday at 5-10 knots.
&&
.MARINE...
Issued at 230 PM EST Wed Jan 24 2024
Webcams were showing some dense fog for parts of the nearshore
waters. High res models support an increase in the thicker fog
tonight. We will therefore issue a marine dense fog advisory.
Winds and waves remain relatively low into the weekend as the
pressure gradient will be relatively weak. The ECMWF is a little
deeper with the low for Friday and would support some higher
gusts.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Dense Fog Advisory until 11 AM EST Thursday for MIZ043>046-
050>052-056>059-064>067-071>074.
MARINE...Dense Fog Advisory until 11 AM EST Thursday for LMZ844>848.
&&
$$
UPDATE...Duke
DISCUSSION...MJS/AMD
AVIATION...Duke
MARINE...MJS
Area Forecast Discussion
National Weather Service Gray ME
738 PM EST Wed Jan 24 2024
.SYNOPSIS...
A series of weak weather systems will cross the region tonight
and again Thursday night with mixed precipitation changing to
rain across the south and along the coast...with light snow and
ice accumulations in the foothills and mountains. A brief break
in the active weather is expected Saturday before a storm system
passes south of New England on Sunday and Monday with some
potential for snow to reach far southern New Hampshire and
southwestern Maine to begin the new work week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
7:35pm Update... Cooled temps for tonight using the HRRR
forecast as the CAD remains strong across all Maine and outside
of far southern and western New Hampshire. Overall the
processes of warming through latent heat are still expected to
occur overnight, but with a cooler starting point ice
accumulations have been brought up slightly with very efficient
accretion rates in the first couple hours of the steady precip.
Ice accretion efficiency drops off quickly as temps get closer
to freezing later overnight, avoiding the higher ice amounts
shown on some raw model output. Overall the message remains the
same with slick travel due to freezing rain and cold surface
temps overnight. Temps creep to freezing outside of central
Maine through daybreak.
Previous...
Weather Impacts: A mix of light snow/freezing rain/sleet may
create hazardous travel conditions through the evening commute
and overnight. Winter Weather Advisories remain in effect.
Details: Our next round of precipitation is approaching from
the west and surface temperatures are slowly warming above
freezing from south to north, in fact areas of southern New
Hampshire near the Massachusetts border are already above
freezing. This gradual warming should help southern New
Hampshire and the far southwestern Maine coast avoid many icing
concerns as they start off as rain or only see a very brief
period of freezing rain. The rest of the CWA will have to
prepare for a potentially slick roads through the evening
commute and overnight. Ice accumulations in most of southern New
Hampshire and just inland from the coast will be less than a
tenth of an inch as the transition to rain will happen fairly
early on in the evening. North of the mountains surface
temperatures should remain cold enough to support more of a mix
of snow and light freezing rain, keeping ice totals closer to a
tenth. The interior and foothills will see the greatest amounts,
closer to two tenths in some areas as light freezing rain will
persist there through most of the night. QPF and rates remain
light so accretion on power lines and trees is not expected to
be significant. The biggest impacts will be to travel as this
has the potential to create a glaze on untreated surfaces.
Anyone on the roads overnight should be cautious of slick
roadways.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
Precipitation will be coming to an end Thursday morning as the
weak 500 mb wave exits and high pressure builds into the area.
Flow turns more northwesterly which will dry us out and keep us
dry for most of the day. Continued southwest flow will help
temperatures climb into the upper 40s south of the mountains and
upper 30s to the north under mostly cloudy skies.
The next surface low riding along the stalled frontal boundary
will arrive Thursday evening. Again we will have high pressure
to our northeast, feeding cooler surface temperatures into the
area, and warm air advection sustaining 850 mb temperatures
above freezing. Therefore, the potential exists for another
messy mix that could effect the Friday morning commute in
places, but more details on this system can be found in the long
term section.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
High Impact Weather Potential:
* Mixed precipitation potential Thursday night into early Friday may
bring travel impacts.
* Low pressure passes south of the region Sunday night into Monday
with wintry precipitation potential for southern areas.
--Pattern and Summary--
A progressive pattern is taking shape across North America this
afternoon with +NAO and weakly positive EPO which has brought a
Pacific airmass across much of the CONUS with temperatures in our
region having recently moved upward after a ~1 week stretch of
temperatures below normal. Through the long term forecast
period...there is strong ensemble guidance support for the PNA
shifting positive which will manifest itself as building heights
across western North America by this weekend through early next
week. This teleconnects to lowering heights across eastern North
America next week which is well-agreed upon in recent
deterministic/ensemble guidance. Between now and then...there will
be two southern stream waves that will bring potentially impactful
weather to our region as long wave troughing marches east across
North America. The first of these arrives to open the forecast
period Thursday night while the second will pass near or south of
the region Sunday and Sunday night. These two systems will be our
primary forecast focus today.
--Daily Details--
Thursday Night - Friday Night: High pressure centered over eastern
Quebec as low pressure over the Great Lakes region weakens as it
pushes into downstream confluent flow across the northeastern United
States. The warm advection push associated with this system will
bring a swath of precipitation that arrives after midnight Thursday
night and continues through the day Friday. A pretty classic cold
air damming setup is evident in the surface pressure pattern with
evidence in the T8s as well. Given that the wave will be weakening
as it pushes into the northeast...warm air advection will also
weaken...with biggest push of warm air aloft remaining to our south.
However...surface temperatures will be warmer than the previous
event. This should allow precipitation to start as rain along the
ME coast and across southern NH up through a LEB-LCI-SFM line with
SN/IP to the north. The freezing line will lift north and east
especially Friday morning...changing precipitation to rain into the
foothills. Given the temperature profile aloft...snow and sleet
will likely be the dominant winter types with less widespread
freezing rain than tonight. QPF is expected to fall in the 0.25-
0.5" range which suggests potential advisory-level impacts for
locations that remain wintry. Expect temperatures in the 30s to
around 40 from north to south by the time we reach Friday afternoon
with precipitation tapering off late in the day and temperatures
settling back to the upper 20s and lower 30s with slick spots Friday
night.
Saturday: While a weak surface high spreads overhead between systems
on Saturday...lingering boundary layer moisture and mid level
shortwave energy may support a few snow showers. However...no
significant weather impacts are expected with relatively mild
temperatures aloft supporting highs in the 30s and lower 40s from
north to south.
Sunday - Monday: Potent southern stream shortwave passes south
of the region during this period with low pressure over the southern
Appalachians Sunday morning strengthening as it passes east north
east and south of the 40N/70W benchmark Sunday night. A review of
the ensemble guidance suggests that the GEFS is less bullish about
bringing precipitation into southern NH/SW ME during the period with
more support for snowfall from the CMC EPS and EC EPS. With these
latter two systems...there are some 30-40% probabilities of 0.5" of
liquid with 10-20% support from the GEFS. Given some potential for
phasing as a northern stream wave dives into the advancing trough
early Monday...confidence the eventual low evolution is only
moderate at this range and is subject to change. There will be a
very dry airmass to our north which will likely yield a sharp
northern edge to any precipitation that reaches our area.
Temperatures are marginal across far southern areas at precip onset,
but snow would be favored if precipitation lingers into Sunday
night. Followed the NBM consensus of likely PoPs reaching the
southern row of counties in NH with chance PoPs further north.
Plenty of time to watch how this evolves...but check back for later
forecast updates as some impacts to the Monday morning commute are
possible...esp over the far south. Improving conditions are expected
Monday with Arctic air spilling in from the north keeping highs in
the teens and 20s.
Tuesday - Wednesday: High pressure builds overhead for Tuesday
before pushing offshore on Wednesday. Thus...expect temperatures
to fall below seasonal norms for Tuesday before rebounding by
the middle of next week. Given the nearby Canadian high and the
dry northwesterly flow trajectory...expect a dry period weather-
wise.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
Short Term...IFR conditions are expected through the overnight
with freezing rain outside of far southern terminals, but
gradual improvement to MVFR will occur heading toward the early
morning as precipitation switches to rain and begins subsiding.
Don`t anticipate much improvement beyond that as another system
is expected Thursday evening, so ceilings likely stay down.
Long Term...A weak system will bring snow and sleet HIE-LEW-AUG
with rain favored for the other terminals Thursday night into
Friday with precipitation slowly changing to rain for LEW-AUG.
Improvement to MVFR/VFR Friday night with a few light snow/rain
showers Saturday bringing isolated restrictions. A stronger
storm system passes south of the region Sunday night and Monday
with restrictions possible for MHT-PSM-PWM in snow or rain and
snow. During the day Monday...a return to VFR is likely with
gusty northerly winds.
&&
.MARINE...
Short Term...Conditions look to remain largely below SCA
criteria through Thursday as seas remain around 2-4 ft. Winds
over the outer waters south of Penobscot Bay remain gusty
tonight with a few infrequent gusts nearing 25 kt. With this
being the case and winds trending down, will hold off on issuing
an SCA.
Long Term...Winds and waves are expected to remain below SCA
levels through Sunday. A strong storm system passes south of the
waters Sunday night and Monday with northeasterly gales
possible depending on how close to the region the storm tracks.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory until 4 AM EST Thursday for MEZ007>009-
012>014-018>028-033.
NH...Winter Weather Advisory until 4 AM EST Thursday for NHZ001>006.
Winter Weather Advisory until 2 AM EST Thursday for NHZ007>015.
MARINE...None.
&&
$$
NEAR TERM...Clair
SHORT TERM...Baron
LONG TERM...Arnott
AVIATION...Arnott/Baron
MARINE...Arnott/Baron
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
745 PM CST Wed Jan 24 2024
.KEY MESSAGES...
* Dense Fog Advisory continues through noon Thursday across all of
central and southeast Illinois. Mild air over a frozen ground
and some snow melt combined with light winds will continue to
favor dense fog through tonight and into tomorrow morning.
* Another round of rain showers will spread in during Thursday and
diminish from the southwest Thursday evening. Yet more rain is
possible by Saturday afternoon into Saturday night.
* Above normal temperatures will continue through early next week,
with even warmer air arriving during the middle and later part
of next week with highs likely in the 50s by next Wednesday.
&&
.UPDATE...
Issued at 745 PM CST Wed Jan 24 2024
Dense fog remains widespread over most of the forecast area,
though there are some locations west of the Illinois River where
conditions have improved to 3-4 miles. Latest HRRR guidance some
of these patches of better visibility may persist into the night.
However, evening soundings from both our office and Davenport IA
show complete saturation up to 850 mb, and a wholesale improvement
in visibility in that area does not appear likely. The more
questionable area may be south of I-70 per latest CAM`s and 18Z
HREF probabilities.
Main changes this evening were to add patchy dense fog over the
forecast area into early Thursday, and adjust timing of the
steadier rain later in the day.
Geelhart
&&
.SHORT TERM... (Through Late Thursday Night)
Issued at 237 PM CST Wed Jan 24 2024
Warm air will remain over the area and with the ground still being
cold and the dewpoints still being warmer than the surface
temperatures, widespread fog and dense fog will be a problem
across the area tonight through tomorrow. An extension of the
dense fog advisory til noon tomorrow has already been issued. If
visibilities begin to increase tomorrow morning, the advisory can
be cancelled early. However, it does appear that the visibilities
should start improving in parts of the area Thursday afternoon
with a better improvement Thursday evening.
The next wave of precip will also move into the area tomorrow
morning, which is slower than previous forecast. This means that
the precip will linger longer into the Thursday night timeframe,
with only a small chance of rain possible in the northern parts of
the CWA after midnight tomorrow night.
Temperatures will remain above freezing through the period, with
the overnight lows being in the mid 30s over most of the area.
With the northwest parts of the CWA still seeing a snow pack, some
locations could be a little cooler. Thursday high temps will be
similar today with lower 50s possible in southeast IL.
Auten
.LONG TERM... (Friday through Next Wednesday)
Issued at 237 PM CST Wed Jan 24 2024
Most of the extended period, Fri through next Wed will be dry with
above normal temperatures. However, another weather system is
expected to move across the the middle Mississippi valley and
bring another round of rain and rain showers to the area Saturday
afternoon through Sat night. Extended models are very consistent
with timing and track location of this system, which presents
higher confidence the the expected forecast. Based on the
forecasted temp profiles with this system, all the precip
initially looks like it will be in the form of rain. In the far
northwest, where the pops are lower, there is a hint that late Sat
night snow could mix with the rain. However, this is when the
system will be pulling away from the area, with the precip ending
before the colder temps arrive.
Daytime temps will remain above normal, with upper 30s to middle
40s expected Fri through Tuesday. With the pattern making a change
the middle of next week, temperatures could warm into the upper
40s to lower 50s by next Wed.
Auten
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 517 PM CST Wed Jan 24 2024
LIFR or worse conditions will prevail through the TAF period, with
ceilings generally in the 200-300 foot range across central
Illinois. Dense fog will also be widespread, though some of the
more recent high-res model guidance has been suggesting a
potential break in the 09-14Z time frame. Morning HREF ensembles
do show some probabilities of >1SM visibility in the 30-40% range
during this period, primarily from KSPI-KCMI. Visibility
improvements are more likely after 18Z, as rain moves into the
area from the southwest.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until noon CST Thursday for ILZ027>031-
036>038-040>057-061>063-066>068-071>073.
&&
$$
Area Forecast Discussion
National Weather Service North Platte NE
540 PM CST Wed Jan 24 2024
.KEY MESSAGES...
*Dense fog tonight, mainly along and east of HWY 83
*Warmer temperatures by the weekend, well above normal by mid-
week
&&
.SHORT TERM /THROUGH THURSDAY/...
Issued at 312 PM CST Wed Jan 24 2024
The main concern in the short term will be the
redevelopment of fog tonight. There will be an abundance of low
level moisture, generally across the eastern portion of our CWA.
This would be along and east of a line from HWY 83. Looking at the
bufkit forecast soundings the RAP, HRRR and the NAM are all in good
consensus of fog developing. The lesser probabilities of dense fog
exist generally to the west of HWY 83, since confidence is low in
just how widespread fog will be, decided to keep them out of a Dense
Fog Advisory and kept them in patchy fog. Did also warm temperatures
slightly, mainly for the eastern portion of the forecast area where
they will be socked in the low clouds all night. Across western
Sandhills did keep temperatures cooler as there is expected to be
some clearing tonight for that location.
As for Thursday, did keep temperatures on the warmer side in the
upper 40s to near 50 in anticipation of clear skies and sunshine for
most of the day. The only exception is across north central Nebraska
where they will be stuck with low clouds and some lingering patchy
fog may remain possible through the afternoon hours, kept temps in
the low to mid 30s.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Issued at 312 PM CST Wed Jan 24 2024
For Thursday night there is the possibility fog may redevelop, a few
models have started to indicate a good signal for fog development,
however was not confident enough to add it into the grids just yet,
but it is something to watch as this could potentially be
another night of dense fog and may need to adjust low
temperatures accordingly if dense fog does develop.
A closed low will track south into northwest KS Friday,
however there could be some wrap around moisture that may impact far
SW Nebraska, thus have put a slight chance of precipitation in
across the far southwest portion of the forecast area, around 15 to
20%. Can`t rule out it falling as freezing drizzle/rain, but
confidence is low as most of the precip should fall south into KS.
Heading into the weekend an upper level ridge begins to build in
across the western CONUS region. As this begins to spread eastward
temperatures will rise above normal with highs in the 40s to 50s on
Monday and upper 40s to even 60 degrees by Wednesday. Precipitation
wise, expect dry conditions in the long term with the exception of
the slight chance of precip Friday.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 537 PM CST Wed Jan 24 2024
Another night of low stratus and dense fog is expected over western
and north central Nebraska, namely along and east of Highway 83.
Main impacts appear to remain east of KVTN, but will need to monitor
for expanding fog potential tonight. Have left any mention of fog
out of KVTN TAF at this time, but will be closely monitoring
visibility overnight.
As for KLBF, the terminal looks to be stuck right on the edge
of the stratus deck and in the lower visibilities. KLBF will likely
remain LIFR through the night. Covering the first few hours
under a TEMPO for 1/4 mile visibility as visibilities have been
fluctuating a bit. Eventually, the dense fog is expected to
settle in, with some slight improvement around sunrise.
Winds remain mostly light and variable through the night at both
terminals, but start to turn northerly near the end of the TAF
period.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory from 9 PM this evening to noon CST Thursday
for NEZ005>010-025>029-037-038-059-070-071.
&&
$$
SHORT TERM...Gomez
LONG TERM...Gomez
AVIATION...Richie
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
602 PM CST Wed Jan 24 2024
.KEY MESSAGES...
- Drizzle, freezing drizzle, mist, & fog continue into this
weekend. Expect slick surfaces late at night through sunrise.
- Drier conditions look likely this weekend, with a few peeks
of Sun possible.
- Very warm temperatures expected for the end of the month into
early February.
&&
.DISCUSSION...
Issued at 221 PM CST Wed Jan 24 2024
Not much change to the forecast is expected over the next few
days, with gloomy conditions persisting through the end of the
week. Low stratus and near-constant mist/fog will continue with
plenty of low-level moisture from above-freezing temperatures
melting the surrounding snowpack, and a stagnant airmass with
the Upper Midwest stuck in the weak flow regime between a
building high over the intermountain west & a low tracking up
the lower Mississippi & Ohio River valleys. The diurnal cycle of
conditions improving as temperatures warm during the daytime, &
degrading overnight as temperatures cool will continue, with
visibilities around 1 mile expected tonight & Thursday night.
Slick roads and surface will also be redevelop tonight &
Thursday with ground temperatures still below freezing, so plan
on a slick & slow commute each morning.
Heavier mist and accumulating drizzle looks likely Thursday as
the precipitation shield from the low to our south slides over
southern Minnesota & western Wisconsin. Precipitation will fall
as drizzle during the daytime, but could change over to some
freezing drizzle across southeast Minnesota & western Wisconsin
early tomorrow morning as well as overnight Thursday into
Friday. Ice accumulation up to 0.1" is possible, especially in
higher terrain areas along the Mississippi & Chippewa Rivers.
Some improvement in the gloomy conditions is expected this
weekend, as drier westerly to northwesterly flow develops
Saturday into Sunday with the western CONUS high pressure
building into the central plains. Mist & some cloud cover is
still likely, especially overnight, as there is still plenty of
snow cover to our west & north to melt. However a few breaks in
the cloud cover look possible during the day along with slightly
warmer temperatures in the mid to upper 30s.
Warmer temperatures really begin to ramp up beginning Tuesday as
very strong ridging for late January/early February builds over
the central CONUS. Ensembles show a strong signal for
temperature anomalies at least 20 degrees above normal, which
would mean highs in the 40s & overnight lows around freezing.
Most of the surrounding snowpack should have ample time to melt
by the time the ridge peaks around the start of February,
meaning surface temperatures should be able to reflect all of
the anomalously high ridging at 500 & 850 mb. It`s still too
early to get a good idea on how warm surface temperatures may be
able to reach, but record high temperatures in the 50s
certainly can`t be ruled out. Any chance for appreciable
precipitation also looks slim to none given the strength of the
ridging overhead. This anomalously warm pattern will peak over
the first few days of February, with ensemble guidance showing a
gradual return to a cooler & more seasonal pattern towards the
middle of February.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 529 PM CST Wed Jan 24 2024
The only place this stratus is going this period is up or down.
We expect another diurnal trend in vsbys/cigs this period, with
both dropping to LIFR/IFR tonight, with minor improvements to
IFR cigs/MVFR vis during the day on Thursday. Biggest
uncertainty tonight is do we see a similar night to last night
with vsbys mainly staying at or above 1sm, or do we go lower
into the fog realm (1/2sm or less). With our snow cover all but
gone, we didn`t see a reason to really deviate much from the
going TAFs and followed the LAV vsbys, with AXN/STC seeing FG,
though this is certainly no guarantee (it`s also no guarantee
that the rest of the MPX terminals will not see fog as well).
For precip, the only location where the RAP is showing
persistent lift (and deeper moisture) is EAU, so that was the
only place we mention precip.
KMSP...Can`t rule out vsbys dropping lower than what we have,
but we aren`t really seeing guidance that says we will be worse
than what we saw last night into this morning, so stayed with
the going TAF. Left precip out tomorrow, with the RAP never
really showing any strong or persistent periods of lift for MSP.
Can`t rule out some dz, but any impacts will not really make
things any worse than the cigs/vis already will be on their own.
/OUTLOOK FOR KMSP/
FRI...IFR likely. Wind WNW 5 kts.
SAT...MVFR. Wind NW 5-10 kts.
SUN...MVFR. Wind NW bcmg SW 5 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
DISCUSSION...ETA
AVIATION...MPG
Area Forecast Discussion
National Weather Service Phoenix AZ
501 PM MST Wed Jan 24 2024
.Update...
00Z Aviation Discussion.
&&
.SYNOPSIS...
A few weak isolated showers will be possible through the
remainder of this afternoon mostly across the higher terrain
areas east of Phoenix with little to no rainfall accumulation
expected. A few areas of patchy fog development will be possible
Thursday morning, but coverage is not expected to be as expansive
as today. A glancing system late Thursday may bring a few isolated
light showers to high terrain areas of South-Central Arizona.
Otherwise, a gradual drying and warming trend begins today with
high temperatures eventually rising above normal by early next
week as high pressure builds in over the western United States.
&&
.DISCUSSION...
Early afternoon WV imagery and objective analysis showed the low
pressure system that brought rainfall to our region is now shifting
into the Texas Panhandle, while drier northwesterly flow aloft now
prevails across the Southwest. Moist boundary layer conditions
remain in place with visible satellite imagery showing widespread
low clouds across south-central Arizona. The HRRR suggests the
possibility of a few weak echoes popping up through the remainder
of this afternoon primarily east of Phoenix, with a few already
showing up near the Pinal/southern Gila County line. Any weak
isolated showers that develop would provide little to no
accumulation before dissipating by early this evening. Looking
back at this morning, places across parts of Yuma, La Paz, and
western Maricopa Counties and along the Lower Colorado River
Valley saw some dense fog development, which has since
dissipated. However, lingering moist surface conditions with dew
points in the upper 40s to around 50 degrees, along with light
winds and decreasing cloud cover, may lead to additional fog
development Thursday morning. Coverage of fog development tomorrow
is not expected to be as expansive as this morning but at least
some patchy fog will be possible. The latest HREF shows the
highest probabilities (up to 30-50%) for localized patchy dense
fog will favor parts of northwest Pinal County, the Imperial
Valley, and potentially along part of I-8 in Yuma County.
Thursday into Friday, a shortwave trough will pass through the Four
Corners region, bringing with it additional rain chances to Arizona.
NBM PoPs keep these chances confined to northern Arizona, while the
highest chances (20-30%) across our CWA will be across the southern
Gila County high terrain. Can`t rule out a weak shower pushing
across northern Maricopa County Thursday afternoon/evening as
suggested by the HREF, but chances for this area to see any
measurable rainfall is less than 10%. Much drier air sets in across
the region in the wake of the passage of the aforementioned
shortwave with ensembles depicting PWAT values falling to around
0.3-0.4". Heading into this weekend, ensemble guidance agree that
an amplified upper level ridge will build across the western
CONUS, leading to warming temperatures and dry conditions
persisting through the first half of next week. Temperatures are
forecast to warm into the low 70s across the lower deserts by this
weekend before further warming about 5-8 degrees above seasonal
normals into the mid 70s early next week.
&&
PREVIOUS DISCUSSION...
The CPC has already advertised it on their socials, but a
breakdown of the ridge leading to another round of unsettled
weather in the West is being projected by long-range model
forecasts toward the start of February. For now, enjoy the
pleasant desert wintertime weather through the middle of next
week, before things potentially take a turn toward cooler and
wetter once more.
&&
.AVIATION...Updated at 2350Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
The SCT cu field has dissipated across the region, resulting in
abundant high clouds which will continue to overspread the region
tonight. Ceilings are expected to lower near sunrise tomorrow
morning with a SCT-BKN cu field developing across the Phoenix
Metro area between 14Z-15Z. Bases will range from ~3-5kft at the
metro terminals, however the potential for MVFR cigs will remain
low (at or below 30%) at KPHX through tomorrow afternoon. It is
more likely bases will be hover around 5kft or higher, however
KDVT and KSDL could see BKN035-040 for several hrs tomorrow
afternoon as a weak disturbance passes N of the area. Winds will
remain very light out of the WSW this evening, before the diurnal
easterly shift occurs by 02Z-04Z. Light winds will continue
through tomorrow afternoon.
Southeast California/Southwest Arizona including KIPL and KBLH:
The main aviation concern overnight and into early tomorrow will
be BR/FG, particularly at IPL. Most high-res guidance and forecast
soundings show FG developing in the Imperial Valley by 09Z-10Z and
lingering until 17-18Z. Therefore confidence was high enough to
introduce IFR vsby/cigs into this TAF package. The chance for low
clouds or fog is very low at KBLH where only a few passing high
clouds are expected. Winds at both terminals will remain light and
variable, with a period of WSW winds expected overnight at IPL.
&&
.FIRE WEATHER...
A gradual drying and warming trend will begin today and continue
through this weekend. There is still lingering surface moisture
this morning leading to high relative humidity values and values
will remain high through at least Thursday night. Thursday night
into Friday morning a passing disturbance will bring a slight
chance for light showers in the high terrain of south-central AZ,
but with near zero chance for wetting rain. The disturbance will
also usher in much drier air in its wake, with minimum relative
humidity values falling to 30-35% Friday and 20-30% this weekend,
where it will remain into early next week. Overnight recoveries at
the end of this week and into early next week will remain good,
at or above 50% most locations. Winds will remain light most of
the time, with the exception of some late morning and afternoon
north to northeast breezes up to 15-20 mph Friday through this
weekend. Temperatures will gradually warm back into the 70s by
this weekend.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Smith
PREVIOUS DISCUSSION...Benedict
AVIATION...Salerno
FIRE WEATHER...Benedict