Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/30/23
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
519 PM MDT Sun Oct 29 2023
...New AVIATION...
.SYNOPSIS...
Issued at 249 PM MDT Sun Oct 29 2023
A mixed bag of winter weather will persist through the remainder
of the day, diminishing after midnight. The best snowfall
accumulations will favor areas across the central mountains, along
with the east central highlands and plains. Gusty east canyon
winds will continue across the middle Rio Grande Valley through
the overnight hours, decreasing before sunrise. A hard freeze is
expected tonight across the middle and lower Rio Grande Valley,
Upper Tularosa Valley, and Chaves County. Temperatures will remain
below seasonal averages through the early week before trending
warmer by mid to late week.
&&
.SHORT TERM...
(This evening through Monday night)
Issued at 249 PM MDT Sun Oct 29 2023
Gap winds have already increased below canyons in the middle/lower
RGV where speeds have reached Wind Advisory at KABQ and below Abo
Pass. The advisory was updated to begin now rather than 6 pm. The
18Z RAP bufr profiles show the cold pool has deepened to near 700mb
at KTCC and KLVS while a strengthening surface high builds down the
Front Range. East winds are likely to persist thru the predawn hours
for the RGV. Meanwhile, the east remains socked in with low cigs and
lingering areas of freezing fog (primarily around Vaughn and Clines
Corners). Current temps are up to 40F below normal with wind chills
in the single digits over parts of northeast and east central NM.
The latest radar loop shows banded rain showers developing west of
the RGV as an upper level shortwave approaches from the northwest.
The main period for accumulating snowfall in the Sangre de Cristos
will occur between now and 9pm as these showers spread northeast.
Confidence is still high that a band of snow will develop early this
evening in the area between I-40 and U.S. 60 from Clines Corners to
Santa Rosa and Encino to Vaughn. A brief burst of moderate snowfall
rates and temps in the low 20s with some blowing snow will lead to
hazardous travel for several hours. Areas along and west of the
central mt chain will see dry air filter in overnight with lighter
winds by sunrise. The coldest temps of the season will occur for the
RGV with a Hard Freeze in many areas. Cigs and vsbys across eastern
NM will improve very slowly thru sunrise while low cigs linger along
the east slopes of the central mt chain Monday morning. Otherwise,
clearing skies will occur by the afternoon with chilly max temps and
lighter winds.
Monday night will be very cold again with clearing skies, light
winds, efficient radiational cooling, and strong valley inversions.
Much of eastern NM will fall into the teens and low 20s with single
digits to low teens over the northern and western high terrain.
&&
.LONG TERM...
(Tuesday through Saturday)
Issued at 249 PM MDT Sun Oct 29 2023
As the system responsible for today`s unsettled weather moves
into the Great Lakes area, a regime of north-northwesterly flow
aloft sets up as ridging builds in its wake. An increase of a few
to 10F can be expected for Tuesday`s daytime highs compared to
Monday`s readings amongst dry and sunny conditions. Low amplitude
ridge builds across the Great Basin Tuesday night into Wednesday,
allowing for pressure heights to rise further. Evening with this,
Wednesday`s daytime highs will be well below average for most
locales for early November. Dry northwest flow will lead to some
breezy conditions across the central highlands and their adjacent
plains that afternoon. The warming trend will continue through the
end of the week, with most locales rebounding a few degrees each
day through the end of the week. A weak backdoor front may offer a
few degrees of cooling for the northeast and east central plains
on Saturday.
&&
.AVIATION...
(00Z TAFS)
Issued at 504 PM MDT Sun Oct 29 2023
The ovc low cigs remain entrenched across all areas along and
east of the Central Mountain Chain this hour. Slow clearing will
progress north to south from the CO border to the I-40 corridor
b/w 09Z to 12Z and down to KROW by 18Z. MVFR/IFR cigs will remain
longer along the east-slopes of the Sandia/Manzano Mts southward
to the east slopes of the south-central mts near KSRR. FZFG will
be possible in these areas with vis restrictions likely. Light sn
or flurries will reach portions of central NM in and around KSAF-
KABQ-KOE0 through 04Z, with a band of light sn develop through
Torrance and Guadalupe Counties. Isold vis restrictions will be
possible from this through 06Z. Meanwhile, strong east canyon
winds at KABQ will continue past midnight. It is not currently
overtopping the Sandia Crest and not expected to do so tonight,
wrapping around the northern edge instead bringing a nly/nely wind
to KAEG. Hi-res guidance suggests an eddy effect setting up in
the ABQ metro area north of I-40, potentially bringing a wly wind
shift to KAEG this evening. This wly shift at KAEG is low
confidence and the take away message for KAEG is that wind dirs
will be tricky this evening and amds may be necessary. Near and
past midnight, the ely winds at KABQ will have a fair chance of
reaching KAEG to becoming the dominate prevailing wind into the
morning. Conditions improve and clear out all areas by 18Z and
onward Monday afternoon.
&&
.FIRE WEATHER...
Issued at 249 PM MDT Sun Oct 29 2023
Significantly colder temperatures, gusty winds, areas of freezing
fog, and some snow over the area today and tonight will clear out by
Monday afternoon. The remainder of the week will feature a warming
trend with relatively light winds, weak mixing, and poor
ventilation.
&&
.PRELIMINARY POINT TEMPS/POPS...
Farmington...................... 21 49 20 55 / 0 0 0 0
Dulce........................... 12 49 10 55 / 5 0 0 0
Cuba............................ 17 44 17 50 / 10 0 0 0
Gallup.......................... 13 51 11 57 / 0 0 0 0
El Morro........................ 17 50 15 53 / 5 0 0 0
Grants.......................... 14 50 12 53 / 5 0 0 0
Quemado......................... 21 53 19 55 / 0 0 0 0
Magdalena....................... 22 46 23 52 / 10 0 0 0
Datil........................... 21 48 22 52 / 5 0 0 0
Reserve......................... 23 58 20 61 / 5 5 0 0
Glenwood........................ 36 60 32 64 / 0 5 0 0
Chama........................... 12 44 12 49 / 10 0 0 0
Los Alamos...................... 22 43 26 48 / 10 5 0 0
Pecos........................... 17 44 21 49 / 30 0 0 0
Cerro/Questa.................... 12 42 13 48 / 50 0 0 0
Red River....................... 8 38 8 45 / 70 0 0 0
Angel Fire...................... 0 39 -3 45 / 60 0 0 0
Taos............................ 14 44 12 51 / 30 0 0 0
Mora............................ 10 43 15 48 / 40 0 0 0
Espanola........................ 21 49 19 56 / 10 0 0 0
Santa Fe........................ 20 43 24 50 / 20 0 0 0
Santa Fe Airport................ 21 46 21 53 / 20 0 0 0
Albuquerque Foothills........... 25 48 28 55 / 10 0 0 0
Albuquerque Heights............. 27 49 27 56 / 10 0 0 0
Albuquerque Valley.............. 26 51 24 58 / 10 0 0 0
Albuquerque West Mesa........... 27 49 27 57 / 10 0 0 0
Belen........................... 25 51 20 58 / 10 0 0 0
Bernalillo...................... 26 50 24 58 / 10 0 0 0
Bosque Farms.................... 23 50 19 57 / 10 0 0 0
Corrales........................ 26 50 25 57 / 10 0 0 0
Los Lunas....................... 25 51 20 58 / 10 0 0 0
Placitas........................ 25 47 27 54 / 10 0 0 0
Rio Rancho...................... 27 49 27 55 / 10 0 0 0
Socorro......................... 27 52 26 59 / 5 0 0 0
Sandia Park/Cedar Crest......... 20 43 24 49 / 20 0 0 0
Tijeras......................... 21 45 21 52 / 20 0 0 0
Edgewood........................ 15 45 14 50 / 30 0 0 0
Moriarty/Estancia............... 13 45 9 52 / 30 0 0 0
Clines Corners.................. 13 40 17 46 / 50 0 0 0
Mountainair..................... 16 45 17 51 / 30 0 0 0
Gran Quivira.................... 16 45 18 52 / 40 0 0 0
Carrizozo....................... 25 48 26 57 / 10 0 0 0
Ruidoso......................... 17 41 22 49 / 10 0 0 0
Capulin......................... 9 41 16 45 / 10 0 0 0
Raton........................... 11 44 14 48 / 10 0 0 0
Springer........................ 12 45 14 51 / 10 0 0 0
Las Vegas....................... 12 41 16 47 / 30 0 0 0
Clayton......................... 16 44 22 49 / 10 0 0 0
Roy............................. 15 41 18 47 / 20 0 0 0
Conchas......................... 20 46 19 52 / 30 0 0 0
Santa Rosa...................... 20 42 18 50 / 60 0 0 0
Tucumcari....................... 19 44 18 51 / 40 0 0 0
Clovis.......................... 22 43 22 52 / 20 0 0 0
Portales........................ 23 44 21 55 / 10 0 0 0
Fort Sumner..................... 23 43 20 52 / 40 0 0 0
Roswell......................... 30 45 27 56 / 10 0 0 0
Picacho......................... 21 41 22 51 / 5 0 0 0
Elk............................. 18 40 21 50 / 5 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 4 AM MDT Monday for NMZ219-220-224-225.
Freeze Warning until 9 AM MDT Monday for NMZ219-220-225-238-240.
Winter Weather Advisory until 6 AM MDT Monday for NMZ213>215.
Winter Weather Advisory until 6 AM MDT Monday for NMZ223-233.
&&
$$
SHORT TERM...42
LONG TERM....12
AVIATION...24
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
615 PM CDT Sun Oct 29 2023
...New AVIATION...
.SHORT TERM...
(Tonight through Monday night)
Issued at 248 PM CDT Sun Oct 29 2023
A cold front will move north to south through Deep South Texas
tonight, Ample instability and synoptic forcing could support a
line of showers with a few embedded thunderstorms along the front.
Behind the front, much cooler temperatures, strong northerly
winds, and lingering showers will continue through the short term.
Confidence is higher with the timing of the front, as both the
NAM and HRRR runs have been handling it well so far. The front
looks to be entering the northern counties around 11 PM and
reaching the lower Rio Grande Valley by 3 AM. Temperatures ahead
of the front in the mid to upper 70s will rapidly fall as the
front moves through, reaching the low 50s by sunrise. Temperatures
will continue to fall through the day Monday, reaching the mid
40s by Monday night.
Confidence is lower on rain chances, as limited moisture could
reduce the concentration and intensity of rainfall. Recent runs of
the CAMs vary wildly, the 3km NAM has a solid line of showers
moving through, while the HRRR and ARW both lean towards a broken
line of scattered showers. Behind the line, isolated to scattered
showers are expected to linger through Monday morning with
chances diminishing after noon. Rain chances increase again Monday
night west of I-69C and along the coast.
A Wind Advisory will be in effect for the barrier islands and coastal
Cameron county from 1 AM Monday to 7 AM Tuesday, with sustained
winds of 25-35 kts and gusts up to 40 kts expected.
Minor coastal flooding is possible this afternoon at local
beaches, a Coastal Flood Statement is in effect until 10 PM.
&&
.LONG TERM...
(Tuesday through next Sunday)
Issued at 248 PM CDT Sun Oct 29 2023
It will quite a chilly start to the start of the long term period
across Deep South Texas with morning low temperatures on Tuesday
(Halloween) expected to fall into the mid 40s and low 50s region
wide. In combination with breezy north winds (sustained around 15-20
MPH), wind chill values will range from the mid 30s across the
Northern Ranchlands to around 40 degrees elsewhere. Students waiting
for the school bus or anyone spending a prolonged period outside
during the morning hours should have a jacket to protect themselves
from the sharply colder temperatures.
Periods of light rain and/or drizzle will continue through the day
on Tuesday as the region remains under the influence of weak coastal
troughing, but there are indications among model guidance that we’ll
start to see precipitation taper off from west to east through the
afternoon and evening hours. This will mean trick-or-treating will
be dry areas generally along/west of I-69 Tuesday evening, with low
chances (20-30%) lingering east of I-69 through the evening. Still,
temperatures will be in the low 50s Tuesday evening with brisk north
winds around 10-20 MPH.
As high pressure settles in Tuesday night into Wednesday and the
pressure gradient weakens, wind speeds will start to decrease and
fall below 10 MPH by Wednesday afternoon. The remainder of the week
will feature a gradual warming trend, with high temperatures
expected warm into the low to mid 80s by the weekend.
&&
.AVIATION...
(00Z TAFS)
Issued at 609 PM CDT Sun Oct 29 2023
VFR conditions will prevail through this evening. Overnight a
cold front will move through the region with winds shifting from
southeasterly to northerly and increasing into Monday. The front
will also bring a chance of rain with a few embedded
thunderstorms late tonight into Monday afternoon which will lead
to MVFR conditions. It is possible that we could see some brief
IFR conditions with this activity, but confidence is too low to
include in this TAf package.
&&
.MARINE...
Issued at 248 PM CDT Sun Oct 29 2023
Tonight through Monday night...A Gale Warning is in effect for the
Laguna Madre and Gulf Waters from 1 AM CDT Monday to 7 AM CDT
Tuesday. The passage of a cold front tonight will bring a strong
northerly wind and rough seas to the Southern Texas coastal
waters. Sustained winds could reach 25-35 kts with gusts up to 40
kts behind the front. These strong northerly winds will likely
build seas in excess of 10ft and create very rough conditions on
the Laguna Madre. Scattered to widespread showers and
thunderstorms are possible through the period, with the greatest
rain chances along and behind the cold front tonight.
Tuesday through next Sunday...Hazardous marine conditions will continue
through Tuesday as northerly winds remain sustained around 25 to 30
knots with wave heights around 8-10 feet or higher. Scattered
showers will be possible as moisture lingers off the coast on
Tuesday, but should end Tuesday night into Wednesday. Small Craft
Advisories will likely be needed on Tuesday. Conditions are expected
to improve Wednesday and remain favorable through the weekend as
high pressure settles in.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE 53 54 47 56 / 40 50 20 40
HARLINGEN 51 52 45 55 / 40 40 10 30
MCALLEN 52 52 47 55 / 30 30 10 20
RIO GRANDE CITY 49 51 45 54 / 30 40 40 30
SOUTH PADRE ISLAND 60 61 53 60 / 50 60 50 50
BAYVIEW/PORT ISABEL 54 55 47 57 / 40 50 30 40
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory from 1 AM Monday to 7 AM CDT Tuesday for TXZ355-
451-454-455.
until 10 PM CDT this evening for TXZ451-454-455.
GM...Gale Warning from 1 AM Monday to 7 AM CDT Tuesday for GMZ130-132-
135-150-155-170-175.
&&
$$
SHORT TERM...60
LONG TERM....22
AVIATION...68
Area Forecast Discussion
National Weather Service Charleston SC
858 PM EDT Sun Oct 29 2023
.SYNOPSIS...
Dry high pressure will prevail through Monday night. A strong
cold front will move through the region Tuesday, ushering in
substantially cooler air. Cold high pressure will then prevail
mid to late week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
No major changes are planned for the late evening update.
Incoming H3R and RAP data and the 29/21z SREF are trending a
foggier across parts of Southeast Georgia overnight with lower
1000 hPa condensation pressure deficits and higher probabilities
for vsbys <1 mile. The latest CONSShort data have not quite
caught up with these trends just yet, so it will be interesting
to see if that model heads in that direction as well. For now,
the forecast is being held steady for the late evening update
until a more definitive and observational trend emerges.
The development of fog and stratus remains the primary forecast
concern overnight, similar to the past few nights. The region
will be positioned along the western flanks of high pressure
centered well offshore. While some degree of increase in the
southwest flow aloft is likely late, model soundings suggest
the boundary layer will remain sufficiently deep to allow full
decoupling with winds going calm/light later this evening.
Clear skies, light/calm winds and very dry conditions atop the
nocturnal inversion are favorable for fog development, but dry
soil conditions and relatively high 1000 hPa condensation
pressure deficits will remain largely supportive shallow fog
layers early Monday. This was verified last night by observers
at both KCHS and KSAV where tower visibilities remaining largely
unrestricted with a multitude of fog banks (some locally dense)
noted. It will be slightly different for areas south of the
I-16 corridor where model condensation pressure deficits begin
to drop <20 hPa after 3-4 AM Monday. Although marginal, this
could be enough to allow for more meaningful fog development
with a relatively higher risk for dense fog, especially closer
to the Altamaha River. "Patchy" to "areas of fog" were
maintained for the early evening update, but a mention of
"patchy dense fog with vsbys 1/4 mile or less" was introduced
for areas south of I-16.
Lows from the mid-upper 50s inland to the mid 60s at the beaches
and Downtown Charleston look on track.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
Pattern Synopsis/Forecast: Highly amplified upper level trough
will be in place across central Canada and down through the
central CONUS early Monday, downstream from sharp ridging along
the West Coast. Surface low pressure will be moving off the New
England coast with an attending cold front that will stretch
down through the southeast CONUS and into the western Gulf of
Mexico. The boundary that separates the wedge of fairly warm air
across the Gulf and southeast CONUS and the surge of
impressively cold arctic air that has overspread much of the
central and western US.
Strong short-wave impulse will dive down through the Northern
Plains/Upper Midwest Monday night and rotate through the
southern Great Lakes through Tuesday night. This will eventually
drive the aforementioned cold front into and through the
southeast states through the course of the day Tuesday into
Tuesday night. But despite the sharp temp contrast across the
boundary, strongest QG- forcing for ascent is still forecast to
be focused well north of our region...up through the Mid
Atlantic into New England while nearly all guidance continue to
show minimal (if any) QPF across our CWA. There still may be a
narrow window for a few showers to develop along the boundary,
particularly late Tuesday afternoon through Tuesday evening, and
particularly across the northern part of the CWA where better
moisture profiles will be in play. We continue to advertise some
very low end rain chances across the tri-county area during
that time...and that has been retained for this forecast.
Otherwise, a pronounced temperature change is in store for
midweek. In the wake of the frontal passage, strong northerly
flow develops Tuesday night and persists through the day
Wednesday. This will deliver substantially cooler and
substantially drier air into the region as H8 temps cool to a
few degrees above 0C heading into Wednesday and PWAT values dive
to under one-quarter of an inch. This will lead to clearing
skies heading into Wednesday. However, despite the sunshine,
temperatures on Wednesday will likely struggle to get out of the
50s during the day. That, coupled with a stout northerly wind
with gusts in the 20 to 30 mph range...and a touch of wind
chill...it will be rather chilly.
Winds: I do not anticipate strong enough gusts to warrant a
Wind Advisory. That said, gusts might get close for a Lake Wind
Advisory on Lake Moultrie on Wednesday.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Large expanse of surface high pressure and very dry air will
build/settle into the Mid Atlantic and southeast states for the
middle to latter half of the work week, resulting in mainly
sunny skies, dry weather and below normal temperatures through
Friday. Coldest day will be on Wednesday with highs in the 50s,
punctuated with a stout northerly wind. Temperatures moderate
through the remainder of the week while winds gradually diminish
Thursday onward.
Overnight temperatures and Frost/Freeze concerns: Forecast low
temperatures in the lower to middle 30s are anticipated
Wednesday night and middle 30s to around 40 for Thursday night.
A few well inland spots could touch freezing early Thursday
morning. However, a persistent northerly surface wind through
Wednesday night is still looking to preclude much frost
formation, at least widespread frost formation. Lighter winds
anticipated for Thursday night, but temperatures will be a
little "warmer." Overall forecast confidence remains too low to
add frost to the forecast at this juncture. But stay tuned...
Late week through next weekend: Surface high pressure will
eventually weaken and migrate into the Atlantic allowing better
moisture and warmer temperatures to slowly edge back into the
region. Some hints in guidance of a coastal low feature
developing off our coast during the weekend timeframe, leading
to shower activity in the coastal waters, although at this
juncture, we believe most if not all of that activity will
remain offshore.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
30/00z TAF Discussion:
KCHS/KJZI/KSAV: Fog and stratus formation remains the biggest
forecast concern for all terminals tonight. For KCHS and KJZI,
fog parameters look similar to yesterday with possibly a bit
more of southwest flow aloft in place atop the nocturnal
inversion. Still think conditions will be supportive of shallow
ground fog layers lurking about both terminals, but the depth of
the fog should remain about 25 ft or less. Vsbys were limited to
MVFR for this reason with 4SM in MIFG at KCHS and 3SM in MIFG at
KJZI roughly 09-12z. For KSAV, the fog situation looks a bit
more favorable with lower model condensation pressure deficits
noted. Still expect several significant fog banks to meander
around the aerodrome in lieu of of one solid, thick fog layer.
This could result in some large swings in conditions as the
layers meander about. For now, prevailing conditions were
limited to 2SM in PRFG from 09-14z with a TEMPO group 09-12z
highlighting a possibility of vsbys dropping right at 1/2SM in
PRFG (airfield minimums). Conditions should quickly improve at
all sites by 13-14z with VFR prevailing thereafter.
Extended Aviation Outlook: Overall VFR. Ground fog will
possible around dawn each morning through Tuesday morning. A
strong cold front will then cross the terminals Tuesday into
Wednesday. In the wake of the front, winds will shift northerly
with gusts 20-25 kts common on Wednesday. Some gustiness will
linger through Thursday.
&&
.MARINE...
Tonight: High pressure over our region will yield tranquil
conditions. Expect sustained winds to be no more than 10 kt.
Lingering swell will gradually subside. Seas should be 1-3 ft
within 20 nm and 3-4 ft for the GA waters beyond 20 nm.
Monday through Monday night: Winds and seas remain below Small
Craft Advisory conditions.
Tuesday and Wednesday: A strong cold front will approach the
region on Tuesday, crossing the Atlantic waters Tuesday night.
In the wake of the front, gusty northerly winds are anticipated
with gusts 25 to 30 knots common across the coastal waters
Wednesday and Wednesday night. A period of gale force gusts are
also possible on Wednesday, primarily in the Charleston
nearshore waters and Georgia outer waters. Along with the gusty
winds, seas will build midweek, peaking between 4-8 feet
Wednesday and Wednesday night. Small Craft Advisories will
eventually be needed for all waters and a Gale Watch/Warning is
possible for the above mentioned areas.
Thursday and Friday: Winds and seas will gradually diminish
Thursday onward. However, with lingering gustiness, an extended
period Small Craft Advisories is possible through the rest of
the week, particularly in the Georgia waters.
&&
.TIDES/COASTAL FLOODING...
Tides will remain elevated through mid week, largely due to
increased astronomical tides, although winds will become more
favorable for increased tide levels by Wednesday. Minor coastal
flooding and Coastal Flood Advisories are possible with the
morning high tide cycles, primarily for Charleston and Coastal
Colleton counties.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1137 PM EDT Sun Oct 29 2023
.AVIATION...
Rainfall associated with an elevated frontal boundary will gradually
come to an end in the 09Z to 14Z. While there has been a trend
toward lowering ceiling heights, many areas have struggled to remain
below MVFR. Several more hours of light rain and additional boundary
layer moistening still supports a prevailing MVFR ceiling with some
intervals of IFR also possible. A little bit of drier air will
filter into the region from the northwest during the late morning
hours as the rain departs to the east. This will boost ceiling
heights to MVFR with the main driver for sustaining the clouds being
the moisture flux off the Great Lakes.
For DTW...Given that the ceilings just south of metro airport have
trended to IFR with these clouds inching northward, a prevailing IFR
cloud deck will be maintained in the metro TAF through daybreak.
.DTW THRESHOLD PROBABILITIES...
* High in ceilings aob 5000 feet tonight and Monday.
&&
.PREV DISCUSSION...
Issued at 814 PM EDT Sun Oct 29 2023
UPDATE...
An update was issued earlier to increase pops and QPF across the
entire forecast area tonight, especially across the north. The
frontal forcing activated a little higher up the frontal slope this
evening, which lead to widespread rain across the Saginaw Valley and
thumb. The most recent RAP is suggesting that the Fgen will become
focused a little farther south during the late evening and overnight
hours. While the intensity will vary across the area, a widespread
light rain will more or less affect all of Se Mi tonight.
PREV DISCUSSION...
Issued at 302 PM EDT Sun Oct 29 2023
DISCUSSION...
A second period of elevated FGEN forcing will expand over the area
late today/this evening as ageostrophic circulation associated with
right entrance region of large anticylonic upper jet shifts through
the region. While some expansion of showers will occur during the
mid to late afternoon hours, most of the light rain from the forcing
will focus during the evening/early morning hours. As was the case
last night, the most persistent activity will set up from the Metro
area southward, but with some shower activity impacting the entire
forecast area this evening. This jet supports shifts eastward very
quickly so coverage of showers will diminish steadily overnight with
little more than scattered lake effect rain showers lingering over
the Thumb region by Monday morning.
Colder and drier air works into the region tonight into Monday as
frontal boundary over area shifts southeast in the wake of the jet
forcing. Highs in the middle 40s on average late today will settle
back largely into the lower 40s on Monday with low temperatures then
dropping into the 20s area-wide on Monday night.
A compact, but very vigorous shortwave will sweep through the area
on Tuesday/Tuesday evening bringing even colder air into the central
Great Lakes. This system will produce scattered to numerous snow or
rain/snow showers especially from late morning hours into the early
evening as main forcing shifts through the region. As mentioned in
the previous forecast, it appears that this wave will be enhanced as
it encounters the relatively mild waters of Lake Michigan Tuesday.
Both forcing and moisture flux will be influenced as some degree of
a mesoscale surface low develops. For SE Lower MI, the best chance
for notable snow showers will occur as the remnants of this smaller
scale feature sweep southeast through/just southwest of the area
around 00z.
All said, at most expect some potential for several tenths of an
inch of wet accumulation on grassy surfaces where the most vigorous
snow showers set up. It is hard to ascertain the most favorable
location for this to occur, but with a trend to focus the mesoscale
enhancement over southern Lake Michigan, perhaps the best potential
for minor accumulations will be in the M-59 to I-94 corridor area
where some enhanced forcing will extend eastward from the actual
vorticity center, particularly over the higher terrain of northwest
Metro area on southwest into the Irish Hills.
Once this system sweeps east, the overall upper troughing over the
area relaxes through the middle of the week with zonal upper flow
setting up by week`s end. This will bring a slow moderation in
temperatures near 40 again Wednesday building towards 50 for Friday.
Shortwave energy will eventually translate through the zonal flow
and produce some buckling to the flow heading into next weekend.
Some chance of rain showers will work back into the area during this
period, but confidence is rather minimal on Day 7 details at this
point.
MARINE...
High pressure continues to move off to the northeast as a weak low
develops over the Ohio Valley. Winds will continue to back tonight
to become northwesterly, with gusts up to 20-25 knots tomorrow.
Small Craft Advisories will go into effect beginning at 3am tonight
for Outer Saginaw Bay and for the nearshore areas from Port Austin
to Port Sanilac. Waves are the primary concern with these
advisories, with wave heights reaching 3-5 feet consistently and
occasionally up to 7 feet. Conditions will drop off later in the day
Monday, as waves are expected to drop below headline criteria in
Outer Saginaw Bay by 10am and for all of the nearshore areas by 4pm.
An upper level trough brings in a surface low pressure system on
Tuesday, which will provide further chances for Small Craft
Advisories on Wednesday. Precipitation can be expected over Lake
Huron from today through the middle of the week. While most of this
precipitation will fall as rain, snow is a distinct possibility on
Tuesday. A broad high pressure will move in behind the low, on
Wednesday, but expect moderate winds to persist over the lake.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory from 3 AM to 10 AM EDT Monday for LHZ421.
Small Craft Advisory from 3 AM to 4 PM EDT Monday for LHZ441-442.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&
$$
AVIATION.....SC
UPDATE.......SC
DISCUSSION...DG
MARINE.......BC
You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.
Area Forecast Discussion
National Weather Service Quad Cities IA IL
859 PM CDT Sun Oct 29 2023
.UPDATE...
Issued at 857 PM CDT Sun Oct 29 2023
Around 8 PM, I updated the sky grids to more closely follow
satellite trends that matched the 21Z HRRR run, and that more or
less delays the clear skies until around 06z in the northwest to
08z around the central areas and 10z southeast. While it is much
slower than earlier forecast, this should still allow for below
freezing temperatures, but may keep us above our lower to mid 20s
levels currently forecast.
ERVIN
&&
.SHORT TERM...(This evening through Monday)
Issued at 240 PM CDT Sun Oct 29 2023
Key messages:
1) Hard freeze tonight into Monday morning ending the growing
season
2) Freeze warning remains in effect from 10 pm this evening to
10 am on Monday
Details:
Dry airmass has kept the pcpn from reaching the ground today but a
wave in the southwest flow was producing rain across western and
central MO. This light rain should clip our se counties through
early this evening. Once this goes by to our east high pressure
then settles into the forecast area overnight and on Monday. This
will bring clear skies and cold temperatures. A hard freeze
expected tonight with lows in the lower to mid 20s at most
locations. This will end the growing season for this year. Highs
on Monday with sunny skies will be in the upper 30s to lower 40s.
.LONG TERM...(Monday night through Sunday)
Issued at 240 PM CDT Sun Oct 29 2023
Key messages:
1) Scary cold on Halloween along with potential for intense snow
showers
2) Warmer temperatures later next week
Halloween (Tuesday): Scary cold with windy conditions and the
potential for intense snow showers. Highs only in the mid to upper
30s. This is about 20 degrees below normal for the end of October.
The intense snow showers will be based on the track of a vigorous
Clipper low pressure system that dives southeast from Manitoba to
southern MN into northern IL. This is associated with a very cold
pocket of air with H5 temps of -40C. Strong PVA/lift and very steep
lapse rates sfc-3km Agl of 8.6C/km and enough moisture would
generate strong to intense snow showers. Minor accumulations on
grassy/elevated surfaces and greatly reduced visibility will be
the main impacts. The last two runs of the GFS have come in
stronger with the system and farther to the west which has
increased our confidence. This will bring windy conditions and
cold temperatures. Northwest winds will be gusting to around 40
mph. The winds should diminish during the evening but for trick-
or-treaters they will need to bundle up, as wind chills will be
in the teens!
Wednesday through the weekend: Global models return a zonal flow
to the forecast area which means a dry stretch with warmer
temperatures. Highs should be in the lower 40s on Wednesday, with
highs warming into the 50s by the weekend. Low confidence on rain
chances as the GFS brings in a stronger cold front by Saturday
night while the ECMWF remains dry.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 609 PM CDT Sun Oct 29 2023
VFR overcast conditions will persist into late evening north to
early morning south. Otherwise, northwest winds will slowly
decrease from around 10 kts this evening to around 7 kts in the
morning hours Monday. Visibility is expected to remain good
throughout the period in dry weather.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Freeze Warning until 10 AM CDT Monday for Benton-Buchanan-Cedar-
Clinton-Delaware-Des Moines-Dubuque-Henry IA-Iowa-Jackson-
Jefferson-Johnson-Jones-Keokuk-Lee-Linn-Louisa-Muscatine-
Scott-Van Buren-Washington.
IL...Freeze Warning until 10 AM CDT Monday for Bureau-Carroll-Hancock-
Henderson-Henry IL-Jo Daviess-McDonough-Mercer-Putnam-Rock
Island-Stephenson-Warren-Whiteside.
MO...Freeze Warning until 10 AM CDT Monday for Clark-Scotland.
&&
$$
UPDATE...Ervin
SHORT TERM...Haase
LONG TERM...Haase
AVIATION...Ervin
Area Forecast Discussion
National Weather Service Goodland KS
1002 PM MDT Sun Oct 29 2023
.SHORT TERM...(This evening through Tuesday)
Issued at 247 PM MDT Sun Oct 29 2023
The light snow band moving over the Tri-state area continues to
weaken as it moves east-southeast. Light accumulations less than an
inch remain possible for those south of a Tribune to Oakley to
Norton line through 5 PM MDT. Skies are beginning to clear over the
western portions of the area, which will allow temperatures to
become very cold tonight. Overnight lows are expected to be in the
upper single digits to the mid teens, with the coldest temperatures
occurring mainly over East-Central Colorado where the higher snow
amounts fell. Wind chills are forecast to fall into the single
digits above and below zero tonight through Monday morning.
Chilly but quiet conditions are expected Monday and Tuesday as high
pressure near the surfaces sits over the Central Plains. Clear skies
are expected both days. High temperatures are expected to be in the
upper 30s to 40s tomorrow and Tuesday, with locally cooler
temperatures possible due to linger snow depths. Overnight lows are
forecast to be in the teens to lower 20s tomorrow night and in the
20s on Tuesday. Wind chills tomorrow night are expected to be in the
single digits across the area.
.LONG TERM...(Wednesday through Sunday)
Issued at 109 PM MDT Sun Oct 29 2023
Continue to expect dry conditions for this part of the forecast. The
upper level short wave troughs continue to track well east of the
region as they deepen, and the jet stream remains primarily north of
the forecast area. Despite it being north of the forecast area, the
flow is quite laminar.
Temperatures will gradually warm through the week due to the jet
stream being to the north of the forecast area. Friday will be the
warmest. Saturday or Sunday another cold front will move through.
The GEFS mean is favoring the faster ECMWF with the trough passage
this weekend, which sends the front through Saturday night. The
operational GFS is slower than the mean, nearly stalling the upper
level trough out over the Central Plains through the weekend. This
brings the front through earlier on Saturday. Currently have more
confidence with the ECMWF/GEFS mean solution of the cold front
moving through later, which is slower than what was seen
yesterday. Am not expecting any precipitation with the frontal
passage.
Models continue to show breezy winds for Friday. Due to the warmer
than normal temperatures, relative humidity values will be less than
20%. Wouldn`t be surprised if the relative humidity values fall
further as the week progresses. Otherwise, Wednesday and Thursday
will have rather light winds with the low relative humidity.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 957 PM MDT Sun Oct 29 2023
VFR conditions remain forecasted at each site for the TAF period.
VAD wind profiler does show some LLWS at KGLD which is supported
as well by RAP forecast soundings. RAP does not suggest this is
ongoing at KMCK so will leave out of the TAF. Winds will become
westerly throughout the night around 7-10 knots. Towards the end
of the period of the period another cold front swings through the
area switching winds back to the NNE; timing differences still
exist so will preclude from introducing into the TAF at this time
due to specifics still being worked out.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...KMK
LONG TERM...JTL
AVIATION...Trigg
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
908 PM CDT Sun Oct 29 2023
.SYNOPSIS...
Issued at 908 PM CDT Sun Oct 29 2023
Rain will come to an end tonight as a cold front gradually shifts
towards the southeast. A few sleet pellets or snowflakes could mix
with rain just before ending. A compact upper system will move
into the area Tuesday afternoon, driving snow showers for parts of
central Illinois, along with another drop in temperatures and
gusty northwest winds which combined will result in wind chills in
the teens by late Tuesday evening.
&&
.UPDATE...
Issued at 908 PM CDT Sun Oct 29 2023
Updates were made this evening to reflect a slight chance (20
percent) of sleet along the back edge of precipitation from around
I-55 westward as numerous reports of mixed precipitation were
received from northern MO, eastern IA, and western IL. Forecast
soundings depicted a deep layer of -5 to -8 C air developing
between 850 and 700 mb leading to sleet along this back edge.
Have not found recent reports of sleet, and will consider not
extending this slight chance of sleet farther east unless more
reports are received. Also delayed clearing given an expanse of
cloud cover to the west. Otherwise, much colder air continues to
slip into the area, with mid 30s already entering the forecast
area, and lows under freezing for most areas north of I-70 still
look on track, and a freeze warning continues for tonight.
37
&&
.DISCUSSION...
Issued at 138 PM CDT Sun Oct 29 2023
------------------------- [Key Messages] -------------------------
1. High confidence (> 80% chance) in sub-freezing temps west of I-55
tonight. Lower (30-60%) chances for a freeze east to I-57.
Greater than a 90% chance for a hard freeze (temps < 28 degF)
area-wide tomorrow night.
2. About a 40-50% chance for accumulating snow along and north of
the I-74 corridor Tuesday afternoon. Accumulations would be
light and travel impacts are not expected.
3. Wind chills in the upper teens to low 20s Tuesday afternoon and
evening as northwest winds gust 30-40 mph. Wind chills will drop
further, into the low teens in spots, Tuesday night when
temperatures drop into the low 20s (upper teens in low-lying
areas).
-------------------------- [Discussion] --------------------------
29.12z HREF guidance suggests cloud cover gradually diminishes from
west to east tonight, with clearing not reaching I-55 until about
07z/2am and I-57 until closer to 11z/6am Monday morning. Meanwhile,
some model guidance is much slower with the departure of those pesky
low clouds; the GFSLamp and ConsShort, for example, don`t have them
exiting to the southeast of the I-55 corridor until after 10z/5am,
which would leave little time (before sunrise) for radiational
cooling. The sky cover forecast was updated using a blend of
GFSLamp, HREF, NBM, and the (most-heavily-weighted) HRRR which is
verifying well with current observations. However, given the
aforementioned diversity of model output, uncertainty surrounds
cloud departure time and hence tonight`s low temperature forecast.
NBM probabilities are generally around 85-100% for < 32 degF
tomorrow morning low temperatures west of I-55, while between I-55
and I-57 those chances span roughly 55-85% (highest northwest). East
of I-57: the chance for those sub freezing lows is 30-55% north of I-
70, but only ~10-25% south. These seem reasonable, which makes the
Freeze Warning a little questionable for several counties where
freeze chances are < 50% tonight. However, locations that don`t see
a freeze tonight will almost certainly (>95% chance everywhere) see
one tomorrow night...so wherever the freeze warning doesn`t verify
tomorrow morning, we`ll reissue for tomorrow night. Hopefully, most
are not counting on one more day to grow their plants anyway.
Along and south of I-70 (where the cold front is stalled) today,
most locations will stay in the 50s for a couple more hours. This
will be the last taste of 50+ degree weather anywhere in our CWA
until roughly Thursday. Behind that cold front, surface high
pressure will gradually build into the region through Monday,
shutting off precipitation tonight and resulting in a period of
light winds tomorrow afternoon and evening.
The next system, a compact upper low barreling southeast from the
northern Plains, will drive a cold front through the district
Tuesday morning and tighten the gradient for gusty northwest winds
Tuesday afternoon and evening when 70% (97%) of the Low Resolution
Ensemble Forecast (LREF) system has 850mb temps dropping to less
than -10 (-8) degC. Bufkit forecast soundings from the GFS and NAM
suggest best mixing Tuesday afternoon will not overlap ideally with
the arrival of the belt of strongest winds aloft (NAM, ECMWF, and
GFS suggest roughly 40kt at 850mb) on the west side of this
disturbance, but all except 2 (of 50) ECMWF members have wind gusts
topping out at 30 mph or higher Tuesday evening at the arbitrarily
chosen sample point of KPIA, and NBM suggests a 45-60% chance for
gusts greater than 35 mph during that time area-wide. Ultimately,
the gustiest winds will be across our northwest CWA Tuesday evening,
with NBM suggesting chances as high as 30-50% (15-30%) for gusts
exceeding 40mph west (east) of the IL River. This is not
particularly unusual for Illinois this time of the year, but it`s
worth noting because (1) temperatures are forecast to fall into the
low 30s Tuesday afternoon (and 20s by mid-late evening) and (2) many
locations are expected to have trick-or-treating during this time.
The combination of strong winds and unseasonably cold temperatures
will result in wind chills in the upper teens to low 20s during the
4-8pm time frame Tuesday evening...with wind chills expected to dip
into the mid teens later. In addition, the gusty winds could be
problematic for Halloween decorations. One more thing to note with
this system: Snow! About 45% of the LREF continues to advertise
accumulations north of I-74, and 15-20% or more members have
accumulations north of a Quincy to Robinson line for the 24-hour
period ending at 7am Wednesday. A couple members from the EPS even
have an inch or more of the white stuff coming down in portions of
Stark, Marshall, Woodford, McLean, Champaign, and Vermilion
Counties. Most of the QPF is forecast to fall during the afternoon
Tuesday when forecast temperatures are in the mid to upper 30s, so
it would be a wet snow with perhaps some rain mixed in, especially
south of I-72; however, those forecast temperatures could be a
little high if precipitation chills the column to lower the height
of the 0 degC isotherm, as often occurs with these cold systems.
It`s uncertain how quickly winds will diminish Tuesday night behind
that system, but NBM is producing splotches of 60-80% probabilities
for low temperatures in the teens Wednesday morning across mainly
our southwest CWA, particularly in the low-lying areas
near/immediately east of the IL River. Temperatures will thereafter
slowly moderate throughout the remainder of the work week, with each
of the deterministic models depicting zonal flow overspreading the
Plains and Midwest Wednesday and beyond. WPC`s clusters suggest some
model diversity by the end of the extended period, with a couple
cluster solutions bringing slight ridging across the Midwest, Great
Lakes, and Ohio Valley, and two other solutions amplifying the ridge
across the West and bringing our area into northwest flow with near
normal h5s. Either way, there`s not much of a hint at unusual and/or
impactful weather this weekend when we`ll all be turning our clocks
back an hour.
Bumgardner
&&
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 633 PM CDT Sun Oct 29 2023
IFR cigs with light rain and mist producing MVFR vsby is
predominant across the central IL terminals as of 00Z. A brief
period of light sleet and snow mixed with the rain is possible
near the end of precipitation as cold air moves in. Improving
cigs should spread slowly southeastward as the system heads off to
the east, with MVFR arriving at KPIA around 01Z, but likely
waiting until around 09Z at KCMI. Continued improvement in cigs
and dissipation of cloud cover should bring VFR conditions
overnight. Winds N-NW 6-14 kts through the period.
37
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
Freeze Warning until 8 AM CDT Monday for ILZ027>031-036>038-
040>057-061-062-066.
Freeze Watch from Monday evening through Tuesday morning for
ILZ063-067-068-071>073.
&&
$$
Area Forecast Discussion
National Weather Service North Platte NE
653 PM CDT Sun Oct 29 2023
.SYNOPSIS...
Issued at 200 PM CDT Sun Oct 29 2023
Key Messages:
- Cold wind chills for Monday and Tuesday morning in the -5 to 5
degF range.
- No tricks, cold night for treats on Halloween as a reinforcing
shot of cold air encompasses the region Tuesday.
- Dry conditions persist through Sunday with temperatures trending
back to at or above normal for the latter half of the week,
generally in the 50s and 60s.
The first winter weather event of the season from yesterday into
early this morning brought narrow bands of heavy snow and light snow
showers to much of western and north central. The core of the narrow
snow bands were not more than 10 to 20 miles wide, resulting in
varying total snow amounts from the event. This morning`s 24 hour
snowfall reports ranged from 1" in North Platte to 2.5" in
Imperial to 5.5" in Big Springs. Please refer to the Public
Information Statement (PNS) from this morning for additional
reports across the area. Though the threat for snow has ended
across the area, folks traveling should remain cautious of the
potential for refreeze of wet roadways, especially during the
overnight/early morning period.
Recent GOES-16 WV and RAP 500-mb analysis showed an elongated trough
of low pressure, extending from western Ontario, southwest into
southern California. This disturbance will continue to advance
eastward today with the trough axis bisecting the Dakota into
northern Nebraska by this evening. Two areas of upper-level high
pressure were noted, one situated off of the Pacific Coast and
another over Florida. At the surface, high pressure holds strong
across the northern Rockies and northern Plains. At 2 PM CT,
temperatures ranged from 28 degrees at Gordon to 32 degrees at
North Platte. Breezy winds have been observed across the area in
response to a tightened surface pressure gradient (SPG) with peak
gusts of 25 to 30 miles per hour. These winds combined with
afternoon temperatures and recent snowfall has resulted in a
rather cold end of October day with wind chill values struggling
to get out of the 20s.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 200 PM CDT Sun Oct 29 2023
The aforementioned upper-level disturbance will continue east into
the Great Lakes region tonight, leaving western and north central
Nebraska in northwesterly flow aloft. Gradually clearing skies are
expected late this evening in response to pressure rises as surface
high pressure nudges further into western Nebraska. Clear skies in
combination with light westerly winds and fresh snow cover will
allow low temperatures to plunge into the teens tonight. Winds will
begin to increase some early morning on Monday ahead of an advancing
cold front. Though gusts of 10 to 15 miles per hour are expected, we
will see the cold wind chill values in the -5 to 5 degF range. By
Monday afternoon, west-northwest winds will be gusting up to 20
to 25 miles per hour. With high temperatures in the low to mid 40s
combined with the expected gusts, wind chills will struggle to
climb out of the 30s through the day. Unfortunately, the cold wind
chills persist as we head into Tuesday thanks to the previously
mentioned cold front sweeping through the area Monday night with
Canadian high pressure building in behind it. Blustery post-frontal
winds out of the north are expected overnight on Monday with
gusts of 25 to 30 miles per hour. By sunrise on Tuesday, winds
will have decreased some, however, will still be enough to create
another morning of cold wind chills. Similar to Monday, anticipate
Tuesday morning wind chills to fall into the -5 to 5 degF range.
Even though these wind chill values remain above headline
criteria, it is the coldest wind chills we will observe so far
this season, so make sure to dress for colder conditions,
especially for any children who have to wait at the bus stop in
the morning. Temperatures only warm into the 30s to low 40s during
the day before quickly falling into the 20s with wind chills in
the teens for trick or treat time Halloween evening. If participating
in Halloween festivities, make sure to bundle up to keep yourself
and the little ones safe from these cold conditions.
.LONG TERM...(Tuesday through Sunday)
Issued at 200 PM CDT Sun Oct 29 2023
On the bright side (at least for those who dislike the cold), the
cold doesn`t stick around for long as upper-level ridging nudges
further northward into the western CONUS on Wednesday. The mean flow
aloft will flatten some on Friday with northwest flow persisting
across Nebraska. As a result, temperatures will moderate into the
at or slightly above normal range, generally in the 50s and 60s
for the latter end of the week. Model solutions vary on the upper-level
pattern come next weekend creating uncertainty in any specific
system impacting the local area. Will need to continue to monitor
trends amongst deterministic and ensemble solutions with
subsequent forecasts should any major changes occur. At this
time, a dry forecast remains in place through the long term
period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 653 PM CDT Sun Oct 29 2023
Lingering snow showers will gradually come to an end across the
region over the next couple of hours. Skies will gradually scatter
out and ceilings will return to VFR. The only major aviation concern
heading into Monday will be stronger westerly winds in the
afternoon. Gusts up to 25 knots are possible before diminishing
Monday night.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Viken
SHORT TERM...Viken
LONG TERM...Viken
AVIATION...Kulik
Area Forecast Discussion
National Weather Service Pueblo CO
618 PM MDT Sun Oct 29 2023
.UPDATE...
Issued at 615 PM MDT Sun Oct 29 2023
Allowed winter wx hilites to expire at 6 pm. Some snow showers
will linger into the early evening before completely coming to an
end. It will clear out and become quite cold tonight with lows in
the 10s plains, 5 to 15 valleys and 5 to -5 higher valleys and
mtns. Can`t rule out some local fog in some locations.
&&
.SHORT TERM...(This evening through Monday)
Issued at 239 PM MDT Sun Oct 29 2023
Key Messages:
1) Snowfall will taper off from north to south this evening, with
all snow expected to end by midnight.
2) Coldest temperatures of the season so far expected tonight into
Monday morning.
Currently...As previously advertised, the focus for the snow has
been gradually shifting south to southeast across the forecast area
this afternoon, with snow coming to an end roughly along and north
of Highway 50. Where snow bands set up earlier this morning, some
impressive snow amounts were reported as was feared, but elsewhere
snow amounts aligned very well with previous ongoing forecast. Temps
warmed into the 20s to around 30F for much of the plains, while El
paso County struggled to reach the mid 20s. The San Luis Valley
warmed into the mid to upper 30s. The HRRR model handled this event
VERY well.
Tonight...Upper longwave trough of low pressure will continue
swinging to the southeast this evening, with all models indicating
that precipitation will end for all areas between 10 PM and midnight
tonight, with the last activity found along the southern CO border.
Cold but dry N-NW flow aloft will push in, helping to clear skies
and dry conditions out for the forecast area. This will lead to some
of the coldest temperatures of the season overnight tonight, with
minimums forecast 5 to 15F above for most areas, and 5 above to 10
below for the higher terrain. Some patchy fog will be a possibility
overnight tonight with clearing skies due to the recent snowfall,
and will pass on this concern to incoming night crew.
Monday...Cool and brisk northwest flow aloft will settle in across
the forecast area for Monday, and dry conditions are expected. The
one challenge will be forecast max temps during the afternoon under
sunny skies. Do not feel that the latest guidance took into
consideration snow amounts, and decided to go on the cooler side for
highs, with readings in the upper 30s to mid 40s. However, will not
be surprised if those areas that received decent snowfall fail to
climb out of the 30s, and will pass this concern on to incoming
crews as well. Moore
.LONG TERM...(Monday night through Sunday)
Issued at 239 PM MDT Sun Oct 29 2023
Key Messages:
1) Dry with a warming trend through the extended period.
Models in good agreement through the extended period with dry and
warming temperatures through the extended period. Northwest flow
behind the departing system will give way to flat ridging for mid
to late week.
Monday night through Tuesday...the region will see broad northwest
flow aloft as an upper trough moves to the east, and upper ridging
builds across the west. Temperatures Monday night will once again
be cold across Colorado given the clear skies, light winds and
lingering snow on the ground. Temperatures will likely fall into
the teens. A few degrees of extra cooling may be possible for snow
covered areas, but will have to see how much and where snow
remains after Monday`s daytime heating. Northwest flow continues
on Tuesday, with with temperatures warming through the 30s to near
50 on the Plains.
Wednesday through Sunday...the upper trough will continue east,
and flat upper ridging will shift across the Rockies through mid
to late week. This will allow for a warming trend to the region,
with highs warming through the 60s and 70s by late week across the
Plains, and 50s and 60s across the San Luis Valley. A weak cold
front is possible on Saturday, with slightly cooler temperatures
on Sunday. Not anticipating any precipitation through this period
of the extended. Mozley
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 239 PM MDT Sun Oct 29 2023
Upper trough will continue pushing across the state late this
afternoon and evening, with the focus of snow shifting to the south.
Snow will begin tapering off from north to south this evening, with
all snow forecast to come to an end along the southern border by
midnight.
KALS: VCNTY snow showers with lowering clouds and vsby will produce
intermittent MVFR-IFR conditions until around 04z. Occasional gusty
E-NE winds to 20kts. VFR conditions expected after 04z.
KCOS and KPUB: VFR to MVFR conditions forecast over the next 24 hrs.
Patchy fog may be an issue and will need to be monitored at both
terminals 05z-14z due to recent snowfall and clearing skies.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HODANISH
SHORT TERM...MOORE
LONG TERM...MOZLEY
AVIATION...MOORE