Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/06/23
Area Forecast Discussion
National Weather Service La Crosse WI
515 PM CST Sun Feb 5 2023
.DISCUSSION...(This evening through Sunday)
Issued at 207 PM CST Sun Feb 5 2023
Key Messages:
- Patchy fog possible tonight as the ridge axis moves overhead
tonight leading to light surface winds.
- Precipitation chances spread into the region beginning late
tomorrow afternoon then quickly exiting to the east by Tuesday
morning. Rain is the main expected precipitation type, but
freezing rain is possible for areas along and north of I-94. A
light glaze is possible, but the window is very brief for
freezing rain. Light snow accumulations are also possible for
areas north of highway 29 up to 1".
- Next system to target the upper midwest mid to late week, but there
is low confidence on how for north the northern edge would
fall across the region.
Tonight - Monday Night...
High pressure slides eastward through the region tonight. With a
deepening light wind layer overnight, there is a chance for fog to
develop across portions of the area. Latest HREF and SREF guidance
would have the higher chances (>80%) for visibilities below 1/4 of a
mile near the SD, MN, and IA borders. For the local area of
southeast Minnesota and northeast Iowa, those probabilities look to
be around 50-60%, but even less (30-50%) for areas east of the
Mississippi River across western Wisconsin and have included patchy
fog into the forecast. With the low level jet increasing in the
early morning hours Monday. Confidence rapidly decreases for any fog
to persist past mid morning.
With the low level jet ramping up over the region by the afternoon,
speeds would near 55 knots at 850 mb from the southwest with the
tightening pressure gradient as shown by the latest RAP guidance.
Warm air advection throughout much of the region will help push
surface temperatures into the 30s by the afternoon ahead of the
approaching shortwave trough. Precipitation is expected to spread
into the region from west to east in associated with a quickly
progressing eastward surface front. Sufficient forcing will result
in rain to fall as the main precipitation type with surface
temperatures above freezing. However, there is a chance for portions
of areas along and north of I-94 to see freezing rain where surface
temperatures remain below freezing and loss of ice occurs aloft.
With how quickly the system is expected to progress through the
region exiting before sunrise Tuesday morning, any ice accumulation
would be very light and very brief for an hour or two sometime
before midnight. Further north of highway 29, accumulating snow is
possible up to 1".
Later half of the work week...
There is still some spread among the model guidance with the timing
and exact track of the next system, so confidence remains low in
determining if any to how much precipitation would fall across the
area as well as the precipitation type. Where confidence is higher
(>75%) is over northeastern Illinois where a majority of the
ensemble guidance would bring the center of the low to track from
the south central plains through the far southern portion of Lake
Michigan. The grand ensemble mean from the EPS, GEFS, and CMC would
have at least 90% member agreement brining measurable precipitation
to the Chicago area by Thursday evening. Even with the higher
confidence off to the southeast of the local area, there is lowered
confidence with the northern extent of this system. Probabilities
quickly drop off further to the northeast from near 65% to 15%.
Where exactly this potentially tight gradient lines up across the
local area is still up for question and will continue to evaluate
over the next several days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 515 PM CST Sun Feb 5 2023
CIGS: as high pressure works across the region tonight, could have a
period of low stratus associated with fog. As flow increases before
12z Mon, clouds should scatter out with a mostly mid/upper level
deck moving back in for late morning. Next upper level shortwave
trough presses in by 00z Tue, with an MVFR/IFR deck likely for much
of mon night.
WX/VSBY: HREF/SREF favor at least MVFR fog developing at the TAF
sites, starting this evening. Mixed signals as to how low the fog
could go though with the HREF holding any sub 2sm at KRST, but the
SREF suggests this would be likely for both locations. For now,
won`t stray too much from previous forecast and monitor. As flow
increases before 12z Mon, vsbys should quickly improve.
Pcpn chances on the increase as a shortwave moves in from the west
by late afternoon. Ice aloft looks to be an issue per NAM/GFS bufkit
soundings, making liquid more likely. Temps progged to be above
freezing for now, but close enough that a period of freezing pcpn
can`t be ruled out.
WINDS: light winds tonight as high pressure scoots across the
region, increase toward 12z, then becoming gusty from the southeast
for Monday.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...Peters
AVIATION.....Rieck
Area Forecast Discussion
National Weather Service Dodge City KS
448 PM CST Sun Feb 5 2023
...Updated aviation section...
.SHORT TERM...(This evening through Monday night)
Issued at 1222 PM CST Sun Feb 5 2023
Near term challenges today will be timing of cold front and
possible fire weather concerns south of this boundary Monday
afternoon. Tonight will need to monitor the potential for fog
across south central Kansas.
A HREF, majority of the CAMS and ensembles today we`re very
similar to yesterday`s run in moving an upper level ridge out into
the plains early tonight as an upper level trough exits the
northern Rockies and moves out into the North Central Plains. As
this upper level trough crosses the plains overnight a cold front
will approach Southwest Kansas. Ahead of this cold front
unseasonably warm temperatures are forecast based on the ECMWF
850mb temperature percentiles along with the majority of the CAMS
boundary layer and 850 millibar temperatures. The increased winds
and warm low-level temperatures will aid in keeping temperatures
up overnight and therefore will trend towards the warmer guidance
for lows tonight. Also trend towards the warmer guidance
temperatures for highs Monday along this cold front location late
Monday afternoon. The most favorable area for these warm
temperatures will be along the Oklahoma border. Further north
Some cooler air will be filtering into southwest Kansas behind
this cold front late day but even taking this into account it
appears that highs in the 50s looks likely based on the good
agreement in the forecast 00z Tuesday 850mb temperatures from all
the deterministic models. Highs in the 40s across west central
Kansas.
A limited area of elevated to near critical fire weather risk
will exist on Monday based on the latest HREF and CAMS. The 12z
HREF Fire Wx probability for RH <20% and winds >15mph for Monday
do highlight locations west of a Meade to Sublette line as an area
where at least elevated fire weather conditions will be possible
given the timing of the cold front as it crosses southwest
Kansas. Multiple CAMS also support this given the timing of cold
frontal passage late day and post frontal winds developing.
As for fog potential tonight...low level moisture will improve
given the southeasterly upslope flow developing across southwest
Kansas. Boundary layer and surface humidity values are forecast by
the HRRR, NAM and RAP southeast of Dodge City which is also where
the HREF cloud ceiling probability <1000ft and probability
visibility <½ are the highest. BUFR soundings by the RAP and NAM
also indicate that this low level moisture returns in the P28 and
possibly HAYS areas late tonight/early Monday. It currently
appears this moisture will primarily stay east of highway 283
(Dodge City). Based on this will only focus the fog potential in
the grids for south central Kansas at this time and let later
shifts expand it further west if needed.
.LONG TERM...(Tuesday through Sunday)
Issued at 1222 PM CST Sun Feb 5 2023
Key messages in the later period:
-Precipitation chances mid week
-Cool end of the week forecast followed by a warmup over the
weekend
Ensembles today still showing the better chance for precipitation
mid week will occur north of a surface cold front and ahead of an
upper level trough which will cross the Southern Plains on
Wednesday. This cold front however is now forecast to be located
across north Texas/Oklahoma as the upper level trough crosses the
Southern Plains. This is further south than what was forecast
yesterday and so now the probability for precipitation as far
north as locations near and east of Dodge City has decreased. Even
given this further south solution we still can not completely
rule out some light precipitation mid week but the confidence of
any measurable precipitation between Dodge City and Pratt/Medicine
Lodge now looks to be less than 30%. Main reason for this low
confidence forecast on precipitation is due to the latest
ensembles location of the 700-500mb deformation zone, probability
24hour Total QPF >0.01 over the past 2 runs and 24-hour QPF
Clusters.
Increasing cloud cover spreading into southwest Kansas mid week
and this cloud cover will linger through late week as a northern
branch upper level wave crosses the Central Plains Thursday. This
northern branch wave may also bring with it a slight chance for
light snow and/or light rain but again little, if any,
accumulation is currently expected. Given the cloud cover late
week combined with a reinforcement of cooler air it looks like
temperatures across southwest Kansas Thursday and Friday will be
below our seasonal normal for this time of year, especially on
Thursday. (Highs in the 40s). Gusty north winds that are also
expected Thursday will make these temperatures feel much colder
than this, especially if the ECMWF ensembles 850mb winds verify.
As for next weekend an upper ridge will begin to build into the
Rockies which would favor ongoing dry conditions but warmer
temperatures.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 446 PM CST Sun Feb 5 2023
VFR conditions will prevail overnight with the exception of around
the HYS terminal where low clouds may infiltrate around sunrise.
These low clouds should quickly burn off by late morning leading
to mostly clear skies for the remainder of the day. Winds will be
from the southeast this evening shifting to a southelry direction
overnight. Winds then shift to the northwest by tomorrow afternoon
as a weak frontal boundary slides through the area.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 35 57 27 48 / 0 0 0 10
GCK 30 53 24 46 / 0 0 0 10
EHA 38 61 26 47 / 0 0 0 20
LBL 35 62 25 48 / 0 0 0 20
HYS 33 54 26 47 / 0 0 0 0
P28 38 64 32 49 / 0 0 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Hovorka_42
forecast discussion alluded to a narrow axis of precipitation and
agree that there will be an opportunity to fine tune chances to a
smaller time window. As for precipitation type, there is a subset of
models suggesting some freezing rain and/or even sleet potential
will exist north of I 69 between 09-13Z Tuesday morning. The setup
passes at least qualitatively as the cold air in the lowest 1.3kft
agl could prove to be extremely difficult to dislodge with freezing
precipitation and latent cooling. The latest operational run of the
05.12Z ECMWF is much warmer in the boundary layer and that also
remains plausible given the strength of the low level jet. Decided
against adding the freezing rain mention out of respect for the warm
advection and with any significant precipitation rate there should
be warm air aloft getting mixed downward from precipitation drag. A
greater mix of types is possible if precipitation struggles to get
going on the front end allowing evaporational cooling to occur.
Amplified and very mild is the theme for the middle of the week as
deep low pressure system is forecasted to track from east Texas
early Wednesday to Lower Michigan by late Thursday. Latest models
show a strong phasing of the northern and southern streams resulting
in strong negative tilt to the shortwave as it arrives. Warm with
temperatures some 15 degrees above normal possible with uncertainty
as to far northward the warm front will progress.
MARINE...
Moderate southwest winds will continue veering northwesterly as a
cold front moves southeastward across the region through this
evening. A stray shower will be possible with the frontal passage,
but mainly dry conditions are anticipated. Enough fetch down the
spine of Lake Huron will allow for elevated waves along the tip of
the Thumb and hazardous marine conditions tonight where ice free
areas remain before decreasing waves and winds become the norm
briefly Monday as high pressure quickly slides across the region.
Marine conditions will then rapidly deteriorate after midnight
Monday night into Tuesday as a strong low pressure system develops
over Hudson Bay and pulls another cold front across the region. A
tightening pressure gradient between the low to the north and the
departing high pressure will result in increasing southerly flow
over the local waters and increasing potential for gales, especially
over the Lake Huron basin. A Gale Watch remains in effect for this
time period across the entire Lake Huron basin, and now includes
Saginaw Bay and all Lake Huron nearshore waters.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Gale Watch from late Monday night through Tuesday afternoon for
LHZ361>363-421-422-441>443-462>464.
Small Craft Advisory from 10 PM this evening to 10 AM EST Monday
for LHZ441.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&
$$
AVIATION.....DG
DISCUSSION...CB
MARINE.......IRL
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
528 PM CST Sun Feb 5 2023
...00Z AVIATION UPDATE...
.SYNOPSIS...
Issued at 100 PM CST Sun Feb 5 2023
Full sun and absence of an arctic airmass over the Upper
Mississippi Valley has allowed temperatures to quickly warm up
into early this afternoon. As of 1 PM, areas south of highway 34
were in the upper 40s to low 50s, locations along I-80 were in
the low/mid 40s, and areas north of highway 30 were in the mid
30s.
&&
.SHORT TERM...(This evening through Monday)
Issued at 100 PM CST Sun Feb 5 2023
Light winds are expected overnight with high pressure overhead.
There is a chance for patchy shallow fog late tonight into early
Monday morning, especially over areas of existing snow cover (north
of I-80).
Monday: As the surface high moves into the Ohio Valley, winds
will increase out of the SE, gusting up to 35 mph during the
afternoon. The gusty winds will advect milder air into the region
once again. Forecast max temps range from the low 50s in the
south to near 40 F north of highway 20.
.LONG TERM...(Monday night through Sunday)
Issued at 100 PM CST Sun Feb 5 2023
[Key Messages]
1) Above normal temperatures favored for much of the long term
2) Precip Monday Night and again Wednesday Night through Friday
[Discussion]
Monday Evening and Overnight...
Moisture and mild air in place will interact with increasing
convergence from the approaching cold front from the west and added
lift from a robust 50+ kt LLJ. The amount of lift above the surface
and presence of steepening mid-level lapse rates above the warm nose
will help generate some scattered light rain showers with the
frontal passage, generating little QPF with very dry air aloft.
Deterministic and ensembles are in good agreement of a widespread
total of a few hundreths to just under a tenth of an inch of rain.
With the frontal passage will have to keep an eye on winds. Fcst
soundings suggest overall mixing during the late afternoon Monday
will remain just below the core of the LLJ, with gusts likely around
25-35 MPH. Once the front passes, we will have some potential to mix
down some stronger wind gusts. Several CAMs like the ARW and NAMnest
hit on this rather robustly but feel they`re a bit overdone as they
feature little in the way of favorable surface lapse rates. HRRR
seems to have a better handle on the potential with very gusty winds
to brief gusts near wind advisory criteria. Don`t have the
confidence to pull the trigger on a headline in this package given
the low confidence on the mixing depth, but will need to watch this
feature heading into tomorrow.
Despite the frontal passage, CAA is rather weak with little in the
way of northwest flow aloft so not expecting too much of a crash in
temperatures overnight. Lows Tuesday morning should only fall to
around 30 into the low 30s.
Tuesday and Tuesday Night...
A quiet day of weather is expected as we will be in between systems
with a surface high quickly moving overhead. Clouds will be slow to
exit but most should see sunshine towards the afternoon. Despite
northwesterly flow the clouds, temperatures will remain above normal
with highs climbing into the upper 30s to mid 40s.
Wednesday through Thursday Night...
Guidance remains on track with increasing potential for an impactful
system across the area Wednesday night into Thursday.
A strong trough / closed low progressing across the Four Corners
region will move east and phase with an upstream shortwave diving
south out of the northern Rockies into the central Plains Wednesday.
Rather robust lift with the phasing shortwaves getting some extra
umph aloft from a weak, but coupled jet streak. This will combined
with a renewed round of strong warm air & moisture advection at the
surface and low levels along with an 850 hPa low to produce
widespread precipitation across much of the Midwest including the
Mississippi River Valley, especially Wednesday night.
As expected, deterministic guidance has started to trend the bulk of
the QPF a little bit eastward and is starting to fall more in line
with their ensemble averages. As previous discussion eluded, rather
moist signal is being indicated in guidance with a good Gulf feed,
with high QPF due to developing TROWEL and def zone. if current
guidance were to stand, precip totals ranging from around a quarter
to potential near one inch will be possible, with the later favored
in locations that see the def zone formation. This is currently
favored in east central Iowa. Thankfully, majority of precip is
expected to remain all rain with a healthy warm nose aloft. North
and west of the Cedar Rapids metro is the most likely area to see
RASN to all SN, but confidence on amounts is low at this time.
Friday on...
Weak shortwave aloft with quite a bit of CVA will follow behind the
departing low pressure, bringing some light snow showers to the area
early Friday. Beyond this, a quiet weekend is in store with high
pressure building back across the Midwest. Temperatures will cool
back down to near normal before southerly flow returns by the
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 528 PM CST Sun Feb 5 2023
VFR conditions will continue throughout the TAF period. The only
exception is for DBQ, where some patchy fog will be possible
tonight. We did consider pulling the MVFR visibilities for the
DBQ TAF completely as forecast models indicate some spread in the
potential for fog to develop. NBM probabilities of MVFR visibility
for DBQ was at around 25 percent, so we will continue to watch
the trends as we approach the 06z TAF issuance. Confidence is
much higher for strong southeast winds to develop Monday, lasting
into the evening hours, ahead of a cold front that will bring
chances of light rain late Monday. Gusts between 25 to 35 knots
are expected.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Uttech
SHORT TERM...Uttech
LONG TERM...Speck
AVIATION...Schultz
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
540 PM CST Sun Feb 5 2023
.DISCUSSION...(This evening through Sunday)
Issued at 222 PM CST Sun Feb 5 2023
Key Messages:
* Low clouds Monday morning most areas, can`t rule out patchy fog
or drizzle far east (Highway 81).
* Above normal temperatures through Wednesday, slight chance for
rain or snow southeastern zones Wednesday (Decreasing chances
from previous forecast).
* Best chance for precipitation this week will be a slight chance
for mainly light snow on Thursday. Snow amounts if any would
likely be light.
* Cool down to end the work week with the Thursday storm system,
but then warming back up into the 40s and 50s next weekend.
Tonight into Monday (Fog and Drizzle Potential)...
We`ve been very warm today and have melted a lot of snow.
Sometimes with light winds you can get fog after a good day of
melting snow, but tonight we should see increasing winds.
Southeasterly winds are expected to increase through the night to
around 15-20 mph after midnight. These southeasterly winds will
bring higher dewpoints into our area, primarily eastern zones
Monday morning.
We expect low stratus clouds to develop and expand into the area
from the south Monday morning. Some of the HRRR runs actually take
the cloud deck all the way to ground and give us patchy dense fog
in our east, but this seems overdone and have left fog out of our
forecast for now, but it will need to be watched. Recent NAM
models also try to generate patchy drizzle Monday morning as
warmer and more moist air flows northward. Most other models (12Z
GFS, ECMWF, and 18Z HRRR) are dry without any drizzle. Will
continue to keep the forecast dry for now as the drizzle/light
rain threat seems better east of our forecast area. If we do get
any drizzle or fog it would be across our far eastern zones east
of Highway 14.
Tuesday through Wednesday (Focus on Wednesday Storm System)
Forecast models continue to come into better agreement in tracking
the Wednesday/Wednesday night upper low further to our southeast,
which would result in dry conditions for most of our CWA. We are
still carrying a slight chance for rain and snow across our far
southeastern zones, but even this is probably overdone given the
continued southeasterly shift in this storm track. The
southeastern track shift is also very evident in the ECMWF
ensemble members. Most likely scenario is that our entire area
will now be dry Wednesday into Wednesday night.
Thursday into Thursday Evening (Best chance for snow)...
We`ll have the next storm system quickly dropping southeast out of
the northern Rockies into the central plains. However, this system
should be fast moving and have limited moisture to work with as it
will not be able to tap into gulf moisture. This system will bring
some colder weather so that the most likely precipitation type
will be snow, but amounts if any would likely be 2 inches or less
for most areas. Of course it`s still several days away and is
currently our best chance for precipitation even though those
chances are only 15-25 percent.
Friday (Cooler Behind Thursday Storm System)...
Cooler air will filter down into the forecast area behind the
departing storm system. Therefore, am currently going for highs in
the upper 30s to lower 40s.
Next Weekend...
The overall pattern remains warm as a trough digs into the western
United States and we see at least somewhat of an upper level ridge
over our area. Highs should climb back into the upper 40s and 50s
for most areas.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Tuesday)
Issued at 525 PM CST Sun Feb 5 2023
Lots of mid level clouds streaming across the area this evening
with light winds mainly out of the south to start the period.
Expect winds to increase out of the south overnight tonight as the
pressure gradient begins to tighten ahead of a weak cold front
which is expected to cross the area during the late morning or
early afternoon hours Monday. As surface winds increase modestly
overnight...winds just above the boundary layer should reach 40-45
KTS...resulting in a 6-9 hour period of LLWS at both terminals.
By daybreak...CIGS should start lowering as the front gets closer
to the terminals...with MVFR or possibly lower CIGS possible by
06/13-14Z. There is some question of potential fog along the
leading edge of this stratus...but think winds will be too strong
at either terminal to result in significant visibility
restrictions with slightly more favorable conditions for fog to
the east of the terminals...with the main impact locally being
the MVFR CIGS which will settle in for most of the day along with
a wind shift around 06/18-19Z that will bring northwesterly winds
to both terminals.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
DISCUSSION...Wesely
AVIATION...Rossi
Area Forecast Discussion
National Weather Service Grand Rapids MI
908 PM EST Sun Feb 5 2023
LATEST UPDATE...
Update
.UPDATE...
Issued at 902 PM EST Sun Feb 5 2023
Radar shows the back edge of the light snow that moved through
earlier has exited the cwa. Looking to the west, IR imagery shows
clearing over the lake and Wisconsin. CONSShort data suggests
that we`ll see some improving cloud cover after 09z and see some
sunshine Monday.
Latest data coming in right now indicates a chance of freezing
rain Monday night along the US-10 corridor. Soundings from the
HRRR suggest sfc temps around 30 with a warm wedge above the sfc.
NamNest also supports this, but the GFS doesn`t. If we do see some
freezing precipitation over the northern cwa Monday night, models
indicate it would be only a 4-5 hr window after midnight.
&&
.DISCUSSION...(This evening through next Sunday)
Issued at 320 PM EST Sun Feb 5 2023
- Showers and gusty winds Monday Night to Tuesday AM with
possible mix/ZR near Route 10 Ludington to near Clare
A cold front will be tracking eastward through the region during
this time. As surge of moisture from the Gulf will advect into
this frontal zone as it moves in. The associated mid level vort
max will also be digging in...so decent lift is possible. The GFS
does show some negative showalter values and the HRRR does
indicate some CAPE as well. Thus we could end up with convective
showers pushing through during this time. We did not add thunder
to the forecast yet as not all models show instability. We will
maintain the high POPs though. With a strong low level jet
accompanying the passage of this system...gusty winds are
expected. Most indications are that 30 to 40 mph values are likely
to occur...but the GFS ensemble values are topping 40 mph. The
soundings support liquid precipitation for most of the area.
However...for interior Lower MI...surface temperatures will be
near freezing...so we will need to monitor the potential for
possible icing. The main risk window for wintry impacts is from
06z to 14z Tue.
- Close call for mixed precipitation Thu into Thu night
The pattern has become a little more favorable for at least a
period of mixed precipitation for interior parts of Lower MI. High
pressure over Ontario will generate northeast winds that will
funnel down some colder air from that region Thursday. At the same
time low pressure will be tracking into Lower MI. Enough cold air
looks present to support at least a period of mixed precipitation.
The relatively warmer air associated with the storm moving in is
expected result in mainly a rain event. However with the northeast
zones being the coldest...the potential impact risk is the highest
there. The precipitation will be steady and possibly heavy at
times. The PWAT values are highly anomalous for this time of the
year. A coupled upper level jet is noted Thursday which will allow
for stronger upper level divergence. A strengthening warm front
along with a 40 to 50 knot LLJ crossing it supports the stronger
low level lift. As a result of all this...there is an increased
potential for more than an inch of qpf from this storm system for
Grand Rapids. This is supported by the 24 hr ensemble qpf trends
from most of the models.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 637 PM EST Sun Feb 5 2023
A well defined upper low is passing over Lower MI attm. There is
some snow associated with it and we`ve seen vsbys fall to 1.5sm in
MKG. The back edge is about to move over GRR and will clear the
terminals within the next few hours. That will leave mostly MVFR
cigs through the rest of the night before rising to around 3500
ft mid morning Monday.
&&
.MARINE...
Issued at 320 PM EST Sun Feb 5 2023
The winds and waves have diminished under criteria for small craft
conditions. Thus we cancelled the advisory. Another marine
headline will be needed for Monday night into Tuesday as the next
front tracks into the marine zones. This system will feature a 50
knot low level jet. The mixing height will be limited though. Most
models show small craft conditions to dominate in this
period...but several models like the GFS and the HRRR are
suggesting gales.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
UPDATE...04
DISCUSSION...MJS
AVIATION...04
MARINE...MJS
Forecast Discussion:
Surface high pressure sits over Kansas today. A mid-level trough
is also positioned over the central US this afternoon. High
clouds have worked their way across central and eastern Kansas
ahead of a weak shortwave trough over the Front Range.
Temperatures in southeastern Kansas are exceeding expectations
this afternoon, approaching the mid 60s in spots. That is well
above our climatological normal of 43 degrees today. A large scale
mid-level trough over the western US will bring changes to our
weather starting tomorrow.
The western system will move across the Intermountain West tonight
and early Monday as a surface trough and cold front approach the
CWA. Strong southerly flow will advect low level moisture northward
over eastern KS, allowing stratus to move in tomorrow morning. Most
model trends are hanging onto cloud cover over far eastern KS into
the afternoon. Efficient WAA should make for another warm day, but
have opted to go slightly cooler than guidance due to possible
lingering cloud cover. South winds will be strong, gusting to near
45 mph in far eastern KS through the afternoon. A line of showers
could then develop along the cold front as it works through east-
central KS tomorrow evening, so have gone with slight chance POPs
near and south of I-35.
The southern portion of the western trough still looks to break off
from the prevailing flow and hold over New Mexico on Tuesday before
kicking out over the southern Plains on Wednesday. I am seeing less
agreement in models on the placement of that system compared to
yesterday so uncertainty in precip chances midweek remain. The GFS
and GEFS are more bullish on rain/light snow development Wednesday
with the low moving over southeast KS. NBM also continues to have 30-
60 percent POPs across the CWA (higher chances in the south and
east). An active and progressive pattern brings another opportunity
for precipitation late in the week with a possibility of some
light snow Thursday night and early Friday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday)
Issued at 513 PM CST Sun Feb 5 2023
Strong low level moisture advection in the low levels is expected
to bring a stratus deck into the terminals around or shortly after
12Z. There is a chance for the stratus to come in below 1000FT but
confidence is marginal. I like the idea from the RAP and GFS
scattering the clouds out by early afternoon given the expected
mixing and depth of the moisture return. Onset and exit of the low
clouds is based largely on the RAP prog.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Teefey
AVIATION...Wolters