Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/24/22
Area Forecast Discussion
National Weather Service Lincoln IL
747 PM CST Sun Jan 23 2022
Issued at 736 PM CST Sun Jan 23 2022
Another fast moving weather system will move through the region
tonight and Monday, bringing a chance of light snow. A few inches
of snow is possible over northern Illinois, with areas close to
I-74 seeing a dusting of snow. Much colder air will arrive behind
this system from Monday night through Wednesday night, with dry
Issued at 747 PM CST Sun Jan 23 2022
Area of light snow is tracking southeast across eastern Iowa this
evening, though surface observations suggest this is mainly north
of I-80 currently. A fairly substantial dry layer was observed on
our evening upper air sounding between 850 and 700 mb, so some
moistening will initially take place as this snow area moves into
the Illinois River Valley toward midnight. Greater snow
enhancement again will be over northern Illinois overnight, with
areas near and north of I-74 being sideswiped. Latest HRRR would
suggest the period from 3-7 am with the greatest potential for any
minor accumulations in this area. Much of the precipitation should
be out of the forecast area before mid morning, though the hi-res
models show some light rain developing toward midday near and
south of I-70 as the front passes. Updates were done to add some
20% PoP`s for Monday afternoon in that area, while minor
tightening of the overnight and early morning PoP`s was done
Winds are starting to shift around to the west/southwest, and our
low temperatures should generally be over the next couple hours.
Temperatures still projected to slowly rise over the CWA after
.SHORT TERM...(This evening through Monday)
ISSUED AT 300 PM CST Sun Jan 23 2022
Mid afternoon surface map shows 1007 mb low pressure near the
OH/PA border with a cold front extending sw through central parts
of KY/AR. Weak 1020 mb high pressure was over northeast MO and
southeast IA and west central IL. MVFR clouds were scattering out
north of I-72 and across southern IL at 3 pm while band of mid
level clouds spreading se from central/western IA and northern MO
into west central IL. Radar mosaic and surface obs show light snow
and flurries have shifted east of CWA into central/northern IN and
far ne IL south of Cook county/Chicago area. Aloft IL remained in
a nw upper level flow with large upper level trof over eastern
North America and upper level high/ridge off the west coast.
High res models bring weak high pressure into southern IL by mid
evening and into the TN river valley overnight, while a clipper
system over the Northern Plains track se through central WI/IA by
late tonight. This will spread a band of light snow into northern
half of IL overnight into Monday morning, especially from I-74
north. Snowfall amounts still appear less than 1 inch over
northern/ne counties from I-74 north with over 1 inch amounts along
north/NE of a LaSalle/Peru to Lafayette, IN northward where
winter wx advisory posted after 3 am tonight through Monday
morning. The light snow could mix with light rain early Mon
afternoon before ending late Mon afternoon. Lows tonight to be
reached this evening in the mid teens northern CWA and lower 20s
south of I-70. Brief warm-up Monday with breezy SSW winds ahead of
the cold front, with highs in the mid 30s from Peoria north and
low to mid 40s sw CWA and southeast IL. With cold front passing
through IL river valley late Mon morning, and through se IL late
Mon afternoon, we will see falling temperatures behind the front
over central IL like what we experienced this morning.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 315 PM CST Sun Jan 23 2022
A strong 1040 mb Canadian high pressure to settle se into the
Northern Plains/upper Midwest Tue afternoon and over MO/IL by
midday Wed. This will bring another cold snap to the area Monday
night through Wed night. Lows Monday night to range from near zero
by Galesburg (wind chills 10-15 below zero) to mid to upper teens
in southeast IL. Highs Tue 10-15 from IL river nw, and mid 20s in
southeast IL and colder wind chills with brisk NW winds. Coldest
air to arrive Tue night with lows in the sing digits below zero
from I-72 north with Galesburg near 10 below, while lows around 5
south of I-70. Wind chills to reach 10-20 below zero Tue night
into mid Wed morning north of I-70, coldest northern/nw CWA where
a wind chill advisory will eventually be needed. Wind chills of 5
to 10 below zero in southeast IL. Another very cold day Wed with
highs in the upper teens to near 20F in central IL and lower 20s
in southeast IL. Lighter winds on Wed as high pressure settles
into the area.
As high pressure shifts into the southeast states Thu, a quick
warm up is expected with breezy sw winds. Highs Thu in the mid to
upper 30s, with sw CWA around 40F. A cold front to push se through
IL Thu afternoon into Thu evening and could bring small chances
of light snow, possibly mixed with light rain Thu afternoon. Not a
lot of moisture to work with this far sw as gulf is cut off and
stronger dynamics are ne of central IL, so any pcpn amounts if
they occur will be light. Colder highs Fri in the lower 20s
northern CWA and upper 20s to near 30 in southeast IL and dry as
high pressure settles se into IL/MO by sunset Fri. But not as
cold as the cold air mass Tue/Wed. Temps modify over the weekend
as high pressure shifts into southeast states and get back into a
south to SW flow. Highs Sat in the low to mid 30s, with upper 30s
from Springfield sw. Highs in the upper 30s/lower 40s next Sunday
with next cold front moving in next Sunday afternoon/evening.
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 527 PM CST Sun Jan 23 2022
Another clipper system will be tracking southeast into the area
overnight. Main visibility impacts will remain further north of
the central Illinois TAF sites, but some heavier snow showers will
bring visibility down to around 4-5 miles at KPIA overnight. While
ceilings go down to around 4000 feet after 06Z, widespread MVFR
conditions should hold off until around midday.
Northwest winds will quickly trend toward the south this evening,
before shifting back northwest behind a cold front late Monday
morning into the afternoon.
Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
813 PM CST Sun Jan 23 2022
Issued at 805 PM CST Sun Jan 23 2022
The forecast trends for tonight look on track. The center of the
surface high is now in southern IL and it will continue to retreat
eastward overnight with increasing south-southeasterly boundary
layer flow in it`s wake, topped by an increasing west-southwesterly
LLJ around 0.5-1.5 km AGL. The resultant WAA regime along with
thickening clouds should stop any additional temperature fall by
midnight or so, and then lead to slowly warming temperatures
The only more prominent change I have made is to add some low pops
for late Monday morning into Monday afternoon, starting in
northeast MO and west central IL and shifting southeast with time.
The RAP, NAM12, and recent runs of the HRRR have been showing
potential for a narrow band of light rain associated with low-mid
level frontogenetical forcing attendant with the cold front.
.SHORT TERM... (Through Late Monday Night)
Issued at 134 PM CST Sun Jan 23 2022
A cold front associated with this morning`s Alberta Clipper has made
its way through most of the forecast area, cooling temperatures from
their morning peaks. A surface high will quickly slide through the
region this evening into the overnight period, the associated calm
winds and clear sky allowing for the best radiational cooling during
the first half of the evening. By the early morning winds will
return to the south ahead of another approaching clipper system, and
the associated WAA along this flow will start to warm temperatures.
This second clipper will follow the same path as the one this
morning, passing through Iowa and northern Illinois, safely north of
our forecast area. Conditions tomorrow morning will be wildly
similar to today. So while the main area of precipitation will be
along and north of the clipper`s low, I can`t rule out some brief
drizzle/freezing drizzle across the northern most CWA as the low
interacts with the WAA.
The area will warm overnight and into the day Monday, before the
attendant cold front associated with the clipper moves through the
CWA Monday afternoon. By the time the cold front makes it to
southeast Missouri and southern Illinois Monday evening,
temperatures will have peaked in the low to mid 50s. The cold front
will usher in an Arctic air mass, causing the bottom to rapidly fall
out of the temperatures. Surface temperatures will drop 30-40
degrees F between noon on Monday to 6am on Tuesday as the robust CAA
cools the lower atmosphere 10-15 C.
.LONG TERM... (Tuesday through Next Sunday)
Issued at 134 PM CST Sun Jan 23 2022
A surface high will move into the region in the wake of the cold
front and, with the Arctic airmass, will linger across the region
Tuesday and Wednesday. 850 mb temperatures will drop into the
negative teens, near the 10th climatological percentile for this
time of year. High temperatures will peak in the teens to 20s across
most of the area and low temperatures bottoming out in the single to
negative single digits Tuesday night into Wednesday.
By Wednesday afternoon the surface high will shift to the east,
throwing the region back into southwesterly flow and a WAA regime,
helping temperatures begin to rebound starting overnight into
Thursday. Southerly flow will continue during the day Thursday
ahead of an approaching mid-level trough and surface low moving
into the area Friday. The persistent dry conditions during the
week appear that they will continue into the weekend. Moisture
associated with this system is very limited, and current forcing
is not expected to be robust enough to produce measurable QPF over
the forecast area. Only a small number of ensemble members
indicate measurable precipitation.
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 538 PM CST Sun Jan 23 2022
The main issue tonight will be a period of LLWS. Surface high
pressure currently centered over the area will retreat eastward
tonight resulting in the development of light southerly winds.
Aloft a west-southwesterly LLJ will bring LLWS conditions for a
period overnight into early Monday morning. Otherwise a mix of
mid-high clouds tonight will bring VFR flight conditions. A strong
cold front will push through the area on Monday afternoon
accompanied by increasing northwest winds. Post-frontal stratus
will bring MVFR flight conditions to KUIN on Monday afternoon, and
these should eventually move into the other terminals beyond the
current valid TAF period on Monday evening.
Area Forecast Discussion
National Weather Service Melbourne FL
925 PM EST Sun Jan 23 2022
...Freeze Warning With Widespread Frost for Lake/Inland Volusia
...Near Freezing Temperatures And Areas of Frost For Much of
the Remainder of the Area...
Temperatures continue their quick post-sunset fall across ECFL this
evening. Already seeing M-U30s across NE Lake/NW Volusia as of 9PM,
with L-M40s southward into Osceola-Brevard and U40s-L50s from Palm
Bay-Melbourne south to Lake Okeechobee and the Treasure Coast where
stubborn low clouds continue to hang tough. Initial temp drop was a
few degrees faster than previously advertised, so made some tweaks
to compensate in the 0-3hr time frame. With T-Td spread narrowing
significantly, nocturnal temp fall should slow in these areas. The
lingering low overcast over the SE CWA will continue to erode from
the N-W, allowing for a steady, slightly faster fall in temps to
Light NW drainage wind expected to drop off toward sunrise as GOMEX
ridge continues to settle SE into FL. 00Z HRRR shows a small piece
of the eastern flank of the ridge pinching off over the peninsula
after 09Z, which would allow for more widespread frost to develop
than is typical for a regime where SFC-H85 winds average near 10kt
as in this case. Overall, the forecast is in great shape, along with
ongoing Warning/Advisory for freezing temps/frost.
.AVIATION...Back edge of the stratus deck (OVC008-012) from just SE
of KMLB to KOBE and continues to plague the VRB-FPR-SUA corridor.
The deck will will continue to erode/dissipate from NW-SE, but do so
slowly. Current timing looks to be about 05Z@VRB, 06Z@FPR and 08Z
@SUA, perhaps an hr later. Otherwise VFR SKC becoming AOA SCT-BKN200
by Mon afternoon.
.MARINE...Given current buoy obs at 41009/41010/41114,winds/seas are
subsiding a bit more quickly than previously indicated. As such will
pare back a little more of the SCA then was scheduled for 02Z/9PM,
changing the nearshore Treasure coast leg to a Cautionary Statement.
Winds/seas across the remaining SCA area will drop below 20KT/7FT by
.PREV DISCUSSION... (Issued 347 PM EST Sun Jan 23 2022)
Monday... Surface low pressure over Texas will continue to build its
axis across the Florida peninsula through the time period, with the
center shifting eastward along the Gulf states and into the Florida
panhandle by the afternoon. Locally, winds will be northwest and
light, with winds around 5 mph or less. After a cold and frosty
start to the day, afternoon highs will only reach in the low to mid
60s areawide. Rain chances will remain out of the forecast through
the time period as forecast soundings show a substantial dry layer
from the low to upper levels with PW values less than 0.30". This
dry air will also limit any cloud development for Monday, with skies
remaining sunny to mostly sunny through the day, with a few high
clouds possible, especially across the north.
Tuesday...A weak area of high pressure crosses the area, allowing
for a chilly morning with clear skies and calm winds. Temperatures
in the low to mid 40s only increase into the upper 50s to low 60s
along and north of I-4, while the Treasure Coast gets a nice warmup
into the low 70s. The next system to impact our area is a a high-
energy mid-level shortwave that quickly crosses the GOMEX Tuesday,
then moves across the FL peninsula Tuesday night. At the surface, an
area of low pressure develops just off the TX coast in the morning,
rapidly crossing the Gulf through the afternoon, then across the
central/southern FL Tuesday night.
The wave quickly shears out depriving the surface low of its needed
upper-level support. Most models indicate the low weakens by the
time it reaches FL, but still brings in significant increase in
moisture. A few showers possible north of I-4 by early afternoon,
then scattered to numerous showers cross the area in the evening and
overnight. Have bumped up rain chances to 60-70pct. Dynamics are not
favorable for lightning storms, but cannot completely rule out a
rumble or two.
Wednesday-Thursday...As a strong ridge across the Northeast U.S.
moves offshore into the western Atlantic, a backdoor front slides
from the Carolinas south to the waters east of FL. This front should
absorb the remnants of the low that crossed FL the day prior, though
some of the guidance does hint at a secondary low developing and
moving east away from FL. Regardless, increasing pressure gradient
and lingering low-level moisture result in scattered onshore moving
showers Wednesday and Thursday as an inverted surface trough
develops. Rain chances are at 30pct for the coast and 20pct inland
on Wednesday, decreasing to 20 pct for the coast and dry inland on
Thursday. Near normal temperatures for mid week, highs ranging up
from upper 60s to mid 70s, and morning lows in the upper 40s to 50s.
Friday-Next Weekend...Models remain in great agreement on the next
significant system moving through the region late Friday as a high
amplitude trough digs into the northern Gulf Coast. Models do not
show a surface low developing anymore, rather indicating a strong
cold front rapidly crossing the peninsula on Saturday. A blast of
cold air behind the front drops temps well below normal next
weekend, with potential for near-freezing temps Sunday morning.
Monday... High pressure ridge will continue to be over the local
area, providing sunny to mostly sunny skies and no rain chances.
Improving boating conditions expected Monday with wind and sea
conditions continuing to improve through the day. Seas will start
off 4-6 ft in the morning before subsiding to 3-5ft by late
afternoon. Northwest winds around 15 KT in the morning will decrease
to around 10 KT by the afternoon.
Tuesday-Friday...Poor boating conditions are likely across the local
waters for much of next week. A weak area of low pressure crosses
the central FL peninsula Tuesday, then pressure gradient over our
area increases Wednesday and Thursday as a backdoor front stalls
east of FL. Scattered to numerous showers with a few lightning
storms are forecast Tuesday and Wednesday, then decreasing Thursday,
with dry conditions on Friday. South/southeast winds around 10KT
Tuesday become north and increase to around 20KT Wednesday afternoon
as the front moves into the local waters. Winds veer NE at 15-20KT
Thursday. Seas 3-5FT through mid week, then swells build to 6-9FT
late Thursday ahead of an approaching strong cold front.
.PRELIMINARY POINT TEMPS/POPS...
DAB 33 62 42 62 / 0 0 10 60
MCO 34 65 45 64 / 0 0 10 60
MLB 36 64 43 67 / 0 0 10 50
VRB 36 67 41 70 / 0 0 0 40
LEE 32 63 44 60 / 0 0 10 60
SFB 35 64 44 62 / 0 0 10 60
ORL 35 65 47 63 / 0 0 10 60
FPR 37 65 41 71 / 0 0 0 40
FL...Frost Advisory from 2 AM to 8 AM Monday for Coastal Volusia-
Freeze Warning from 2 AM to 8 AM Monday for Inland Volusia-
Northern Lake-Southern Lake.
AM...Small Craft Advisory until 4 AM Monday for Volusia-Brevard
County Line to Jupiter Inlet 20-60 nm.
Area Forecast Discussion
National Weather Service Mount Holly NJ
906 PM EST Sun Jan 23 2022
Several weak clipper systems will pass across the region
tonight through Tuesday night. Strong high pressure builds in
from the west Wednesday through Thursday, then moves offshore on
Friday. A potential coastal storm may affect the region next
.NEAR TERM /THROUGH MONDAY/...
The first bit of light snow put down a sporadic 1/2 inch to an
inch west of the I95 with mainly trace amounts along and near
it. The back end of the light snow is moving off the coast now.
A few 1/10ths could accumulate in spots across Ocean south
through Atlantic county.
The second batch of snow to our west is decaying as expected,
but more quickly. The HRRR is suggesting only the southern
Poconos will pick up any additional accumulation.
The cold air advection is not expected to be particularly
strong tonight, so temperatures probably won`t be much different
than Saturday night south of I-78 (around 15- 20 degrees).
Single digits are expected in the southern Poconos and far
northwest New Jersey though. Skies will begin to clear overnight
On Monday, a surface ridge axis will pass through the region
with the flow turning southerly in its wake late in the day.
Expect high temperatures mostly in the 30s (mid to upper 20s in
the southern Poconos and northwest New Jersey) and a light
breeze. Skies will be mostly clear during the daytime, but will
start to increase again later in the day as the next clipper
system approaches from the west.
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/...
A weak clipper system moves through the Great Lakes Monday
night and should be over Lake Ontario by Tuesday morning before
lifting through northern New York state and into eastern Canada
during the day Tuesday.
A strong vort max passes through eastern Pennsylvania and
northern New Jersey just ahead of the clipper Monday night, and
although conditions will be fairly dry with surface dew points
in the teens, it should be enough to kick off some light snow
across the southern Poconos and northern New Jersey, and
possibly down into the Lehigh Valley. Although QPF will be
minimal, generally a few hundredths of an inch, snow ratios will
be around 15-20:1. As much as 1-2 inches of snow will be
possible across Carbon and Monroe counties, and less than an
inch down to the Lehigh Valley.
Another shortwave will rotate around the departing clipper
system. The base of a deep H5 trough will extend down to
Tennessee Valley and Southeast, and models indicating a weak
area of low pressure forming around the Mid-Atlantic area. This
may touch off some more precip in the late morning and early
afternoon. In terms of ptype, snow is possible to the far north,
while a wintry mix is possible for most of the rest of the
area. Precip should change to rain in the late morning south of
the Fall Line.
Lows Monday night will range from the teens up north to the 20s
otherwise. Highs on Tuesday will range from the 30s up north to
the 40s south of the Fall Line.
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Cold front passes through Tuesday night and any lingering
precip tapers off early in the evening. Strong cold air
advection will spread into the region starting Tuesday night.
Canadian 1038 mb high pressure then builds in from the west and
will be centered over the Midwest on Wednesday before moving
nearly overhead on Thursday, and then out to sea on Friday.
During this time it will be cold and dry with below normal
temperatures. Highs will be in the 20s to low 30s Wednesday and
Thursday before warming closer to normal by some 10 degrees on
Going into the end of the week, a deep, positively H5 trough
will dig through the nation with the base of the trough digging
into the Gulf Coast by Friday. Surface low pressure develops out
ahead of it over the Southeast, then lifts towards the Mid-
Highly uncertain as to what happens from there. The 12Z GFS and
the 12Z ECMWF has a far offshore track with the low, whereas
the 12Z CMC is much closer to the coast with a significant
snowstorm. Will continue to follow the NBM guidance with slight
chance PoPs throughout and low chance PoPs along the New Jersey
shore. Will also point out that all members but one of the GEFS
keep the storm offshore.
For the most part, the last several runs of models have overall
kept the storm offshore, but there have been a few runs,
including the 12Z CMC, that bring it much closer to the coast
with the potential for significant impacts. While chances are
increasing that a storm will develop next weekend, it remains to
be seen exactly where it will be. It will take some time over
the next couple of days for the models to pick up on the details
that will show whether it will track offshore or closer to the
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.
Through 06Z...Snow showers will remain isolated and light. Some
visibility restrictions to MVFR are expected at times, mainly
at RDG and ABE. Light and variable winds. Moderate confidence.
Overnight...VFR with lower ceilings beginning to lift and
scatter out through 12Z. Winds becoming northwesterly around 5
kts or less. High confidence.
Monday...VFR with scattered mid-level and cirrus clouds. Winds
initially north to northwesterly around 5 kts. Winds will become
light and variable around 18Z then settle out of the south
between 21-00Z around 5 kts or less. High confidence.
Monday night...VFR overall, but some light snow showers
possible at KRDG/KABE with brief sub-VFR conditions. S winds
less than 10 kt. Low confidence.
Tuesday...VFR overall. A light wintry mix possible in the
morning with snow possible at KRDG/KABE, and the wintry mix
could change to plain rain by late morning. Overall chances are
fairly low. Brief, sub-VFR conditions possible in precip. W
winds less than 10 kt. Low confidence.
Tuesday night through Wednesday night...VFR. NW winds less than
10 kt Tuesday night, increasing to 10 to 15 kt with gusts up to
20 kt Wednesday, becoming N less than 10 kt Wednesday night.
Thursday...VFR. LGT/VRB winds, becoming S less than 10 kt. High
Friday...VFR. W winds less than 10 kt. Moderate confidence.
No marine headlines are anticipated through Monday. Winds
southwest to west around 10-15 kts. The winds will then shift
gradually to north to northwesterly overnight then shift
southerly late Monday afternoon and evening. Seas around 3-4
feet. A period of light snow is possible late this evening north
of Atlantic City.
Monday night...Overall, sub-SCA conditions, but a few gusts to
25 kt possible on the ocean and seas may briefly build close to
Wednesday...Occasional NW winds gusting to 25 kt possible.
Thursday through Friday...Sub-SCA conditions.