Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/04/20
Area Forecast Discussion
National Weather Service Cheyenne WY
528 PM MDT Sun May 3 2020
.SHORT TERM...(This evening through Tuesday night)
Issued at 240 PM MDT Sun May 3 2020
Cold front moving in western Wyoming this afternoon. Out ahead of
the front...seeing a few storms developing across southwest Carbon
County. Observing a few cells percolating over the mountains near
Red Feather Lakes area. Most of the CWA dry at the moment...but do
expect conditions to change as we get further into the afternoon.
Latest HRRR and Hires guidance showing next hour or two that
convection increases across Carbon County...spreading east into
northern Platte and Goshen Counties. SPC Mesoanalysis page
showing surface based CAPE increasing to 1500 J/KG near Wheatland
and Torrington up to near 2500 J/KG near Alliance. Shear values on
the order of 45-55kts 0-6km across the Panhandle...so looks like
we are still under the threat of severe thunderstorms out there
this afternoon. Latest HRRR simulated radar continues to focus on
the northern Nebraska Panhandle for severe storms this afternoon.
Then increasing chances for more widespread showers and isolated
thunderstorms well into the evening and overnight.
Upper shortwave with the front looks to move through to the east
after 15Z or so Monday. Though ECMWF a bit slower...more like
18-21Z or so. So did hold onto PoPs through the morning hours
Monday before ending from west to east Monday afternoon.
Warm/dry for Tuesday as upper ridge builds across eastern Idaho
and western Wyoming. We stay in northwest flow through the
day...though still dry. GFS hinting at possibly the intrusion of a
surface cold front Tuesday afternoon into the northern Panhandle
and parts of Niobrara County. This would lead me to believe we
could see a few showers/thunderstorms Tuesday afternoon. For
now...kept the forecast dry.
.LONG TERM...(Wednesday through Sunday)
Issued at 240 PM MDT Sun May 3 2020
Upper ridging will be the primary weather feature affecting the
CWA this period providing generally dry and mild conditions.
There will be a couple shortwaves to affect the CWA, the most
significant one passing by to the north Weds night bringing some
showers to mainly northern parts of the CWA as well as driving a
cold front across the area Thursday. Rather cool conditions in the
wake of the front Friday and Saturday under northwesterly flow
aloft with maybe a few showers in association with any weak
impulses that may affect the area.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 521 PM MDT Sun May 3 2020
Wyoming TAFS...VFR at Rawlins until 08Z, with occasional
thunderstorms producing gusts to 30 knots until 02Z, and
occasional showers producing MVFR from 06Z to 08Z. then MVFR until
15Z, then VFR. Wind gusts to 35 knots after 18Z Monday.
VFR at Laramie until 09Z, with occasional thunderstorms producing
gusts to 35 knots until 03Z, then MVFR until 15Z, then VFR. Wind
gusts to 22 knots after 15Z, and to 35 knots after 18Z.
VFR at Cheyenne until 07Z, with occasional thunderstorms producing
gusts to 35 knots until 02Z, then thunderstorms in the vicinity,
then MVFR until 14Z, then VFR. Wind gusts to 26 knots after 12Z
Monday.
VFR at Chadron and Alliance until 10Z, with occasional
thunderstorms producing gusts to 35 knots until 03Z, then MVFR
until 17Z, then VFR. Wind gusts to 32 knots after 17Z Monday.
VFR at Scottsbluff until 05Z, with occasional thunderstorms
producing gusts to 35 knots until 03Z, then MVFR until 18Z, then
VFR. Wind gusts to 30 knots after 18Z Monday.
VFR at Sidney until 09Z, with occasional thunderstorms producing
gusts to 35 knots until 03Z, then IFR from 09Z to 12Z, then MVFR
until 15Z, then VFR. Wind gusts to 31 knots after 12Z Monday.
&&
.FIRE WEATHER...
Issued at 240 PM MDT Sun May 3 2020
Look for showers and thunderstorms to increase in coverage this
afternoon and continue overnight...as a cold front approaches
from the west. Good chances for wetting rains for most locations.
Mountains are already seeing measurable rainfall that will turn
over to snow at the highest peaks. Upper low moves through to the
east Monday with showers ending from west to east through the day.
Drier pattern for Tuesday through the upcoming week as high
pressure builds into the area.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...GCC
LONG TERM...RE
AVIATION...RUBIN
FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Dodge City KS
448 PM CDT Sun May 3 2020
...Updated Aviation...
.SHORT TERM...(This evening through Monday)
Issued at 359 PM CDT Sun May 3 2020
A quasi-stationary frontal boundary at the surface extended across
southern into northeastern Oklahoma this afternoon. Along this
front, surface dewpoints of 64-68F were pooling. There was quite a
bit of low level moisture north of this front as well, with
observations showing upper 50s dewpoint as far northwest as Gage and
Alva, OK. Winds in these areas were still out of the northeast,
however they will continue to veer around to the east and eventually
southeast tonight. This will begin the significant moisture
advection back into western Kansas. Dewpoints will rise through the
50s all night leading to widespread low stratus cloud development.
Some areas of fog will also develop, although dense fog is currently
not anticipated given enough boundary layer mixing. After midnight
the low level jet will increase out of the south, and we will likely
see fairly widespread drizzle development within the rich moist
axis. The near-surface moist layer will be at least 1km deep with
good directional shear to generate the necessary turbulent mixing
atop the moist layer for at least moderate drizzle.
As far as thunderstorms go overnight, the best risk for this will be
just north of our forecast area, north of I-70 across far northern
Kansas into adjacent southern Nebraska. A mesoscale convective
system is likely to evolve after midnight and continue through the
early morning hours Monday, again most likely tracking just north of
our forecast area. The southern most storms could skirt Trego and
Ellis County, so this will need to be watched closely. The damp
morning will eventually give way to drier conditions as north-
northwest winds push in behind the exiting storm system to our
north. The strongest cold advection will be up in our northeast and
may be augmented by the bubble high behind the expected MCS.
Temperatures up in our far northeast will be tricky tomorrow. The
NAM12 has a 21z temperature of 59F at Hays while the earlier HRRR
12z run had mid 80s! The more recent 18z run of the HRRR shows a
stronger MCS signal and subsequent cooler temperatures in its wake
across Ellis County. Officially, we will be going with around 68F
for a high at Hays with lower 80s from Elkhart to Hugoton to
Liberal.
.LONG TERM...(Monday night through Sunday)
Issued at 359 PM CDT Sun May 3 2020
The rest of the week will be fairly quiet. Tuesday will be quite
enjoyable with high pressure at the surface centered over western
Kansas, thus very light winds much of the day and pleasant
temperatures in the 70s lower to mid 70s for highs. We will warm
back up to the upper 70s to lower 80s Wednesday and Thursday before
the next front moves in Thursday Evening. This will also be the next
chance for thunderstorm activity, however much of southwest Kansas
is likely to miss out on this thunderstorm activity like previous
fronts. If the front is slower like the GFS model shows, then much
more of southwest Kansas will see a chance for storms, however the
ECMWF looks much different with a faster front and all the
strong/severe thunderstorm risk across Oklahoma and south
central/southeast Kansas. Our official forecast will have 20-30 POPs
late day Thursday/Thursday evening mainly southeast of a Meade to
Bucklin to Pratt line. The airmass behind this front late-week will
be rather cool, so Friday temperatures will likely only top out in
the mid 60s with only a slow rebound back into the lower to mid 70s
over the following weekend. The long term meteorological pattern for
May 8-11 and perhaps beyond does not look favorable for widespread
severe weather affecting southwestern Kansas (longwave trough
focused on the eastern CONUS and ridging out west).
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 448 PM CDT Sun May 3 2020
High confidence of rapidly degrading flight categories tonight,
with strong moisture advection saturating the boundary layer. All
models generate widespread IFR/LIFR stratus cigs during the
06-15z Mon time frame. Areas of drizzle or mist will also limit
surface visibility. Latest iterations of HRRR suggest convection
will remain north of HYS, so will not include in TAFs overnight.
Not confident on extent of fog development, so kept visibility
reductions modest for now, at 1-2 sm in BR/DZ. A strong cold front
will quickly return VFR/SKC to the airports around 18z Mon,
followed by strong NW winds gusting 30-35 kts.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 77 50 74 / 20 10 10 0
GCK 57 80 48 74 / 20 10 10 0
EHA 57 84 51 72 / 10 10 20 10
LBL 58 83 49 73 / 10 10 10 0
HYS 54 68 45 74 / 40 20 0 0
P28 59 76 52 75 / 20 20 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...Turner
Area Forecast Discussion
National Weather Service Huntsville AL
810 PM CDT Sun May 3 2020
.NEAR TERM...(Tonight)
Issued at 809 PM CDT Sun May 3 2020
Impressive MCS has now exited/dissipated as it pushed into a more
stable/drier environment over GA and east TN. The MCV is still
visible on radar in east TN from earlier large bow echo that rolled
through west and middle TN. The southern end of this cold pool
pushed south into our southern middle TN and north AL counties
producing widespread wind damage, mainly north of the TN River. In
fact, MSL, DCU and HSV received no measurable rain behind the gust
front! The thunderstorms that redeveloped in southwest TN have fallen
apart for the most part, with just a few showers remaining. Inflow
CAPE of 500-1000 J/Kg may still enable a few additional storms later
tonight along the cold front as it drops south. However, latest HRRR
runs are not too impressive with this redevelopment and in fact
dissipate it as it reaches our area. Will lower PoPs late tonight
with this trend in mind, but not remove completely.
.SHORT TERM...(Monday through Tuesday Night)
Issued at 215 PM CDT Sun May 3 2020
Any lingering precip from the previous night should be waning before
sunrise as a weak cold front shifts south. Guidance looks to push
the front south of I 565 but north of I 20 before stalling out. With
the CWA adjacent to this boundary, models continue to show a
destabilization trend heading into the late afternoon/evening hours
tomorrow. The big question remains whether or not we can get any
storms going tomorrow. Minimal upper level support will be
available so any activity will have tap into some low level
convergence areas, which could be enhanced with the surface
boundary. So if some storms do get going late afternoon and into
the evening, we could see some strong wind gusts and hail.
Convective activity will wane as we move into the early morning
hours of Tuesdays and temps drop into the mid 60s. After sunrise,
another cold front will be quickly approaching the area from the
west. Expect a similar story compared to Monday where the atmosphere
will have plenty of instability to tap into (if able to overcome the
cap) but limited forcing and marginal upper level support. Most
forcing as it appears now will come from the front itself as it
pushes in by late Tuesday afternoon. Main impacts from any strong
storms would be gusty winds and hail.
The front quickly moves south after sunset on Tuesday with a slow
decrease in cloud cover through the night. Temps overnight will drop
into the low/mid 50s.
.LONG TERM...(Wednesday through Saturday)
Issued at 215 PM CDT Sun May 3 2020
A cooler and drier pattern will be in the forecast Wed through Thurs
in the wake of the previous day`s cold front. Benign conditions and
comfortable afternoon temps in the low 70s can be expected. We`ll
see the pattern start to shift by Friday as the next frontal system
is progged to move from the Central Plains through the Ohio Valley
by Friday. The attendant cold front will start to move into the SE
US Friday morning. With a surge of moisture from the southwest ahead
of the front, rain chances will increase by the late morning on
Friday and linger until the front passes well south early Sat
morning. Thunderstorm parameters with this system do not look
conducive for any development, so will maintain shower wording in the
forecast.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 608 PM CDT Sun May 3 2020
Although VFR conditions will prevail this evening, additional TS
developing in western TN will drop southeast into north AL this
evening, possibly affecting KHSV and KMSL areas. If these arrive, a
brief period of gusty winds and IFR conditions are possible. Lower
clouds may develop late tonight into early Monday producing IFR
conditions through late Monday morning. A frontal boundary will
stall over the area through Monday which may produce additional TS as
well.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
NEAR TERM...17
SHORT TERM...Barron
LONG TERM...Barron
AVIATION...17
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Lincoln IL
737 PM CDT Sun May 3 2020
.SYNOPSIS...
Issued at 602 PM CDT Sun May 3 2020
Mostly clear skies are expected across central Illinois tonight
and early Monday. However, expect an increase in clouds through
the day Monday, ahead of the next weather system. This next system
may bring some light rain by mid to late afternoon, but most of
the rain is expected Monday night.
&&
.UPDATE...
Issued at 737 PM CDT Sun May 3 2020
Forecast was updated to increase the winds across the northern
half of the CWA after midnight.
Latest surface observations showing a "pneumonia front" (backdoor
cold front) riding south along the Lake Michigan shoreline just
south of Milwaukee, with a 25-30 degree temperature drop as winds
shift off the lake. HRRR model shows this plowing across the
Chicago metro later this evening, reaching the I-74 corridor
around 2-3 am. Temperature impacts will become more mitigated as
the front gets this far away from the lake, but a strong wind
shift to the northeast and some gusts of 15-20 mph should make it
this far south.
&&
.SHORT TERM...(This evening through Monday)
ISSUED AT 243 PM CDT Sun May 3 2020
Light showers will linger across the area late this afternoon,
with remaining into early evening in eastern IL. Clearing skies
should also move from west to east early this evening. A high
pressure ridge will move across the area tonight through tomorrow
morning with very dry conditions. Combined with light winds and
temps should drop back down into the low to mid 40s. The next
system moves into the CWA beginning tomorrow afternoon. The
associated sfc low pressure area will be south of the area while
the mid level system will be to the north. The trough/short wave
associated with the system as it moves across the area will bring
showers and isolated storms to the region. Any thunderstorms
should remain across the southern part of the CWA. Temps should
get into the 60s tomorrow before clouds and precip arrive.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 243 PM CDT Sun May 3 2020
Precip will continue and be likely Monday night as the
trough/short wave moves east through the area. Most of the precip
will be Mon night but amounts will be quite low given the fact
that central IL will be in between the two best areas of
forcing/moisture. With mid level troughiness building after this
system, a chance of showers will remain across the area for Tue
through Tue night with a small chance on Wed. After a brief period
of dry weather Wed night and Thur, more precip arrives into the
area for the end of the week. This system is a little stronger and
chances are better for precip for Thur night and Friday. Drier and
much cooler weather is then expected for the weekend. After temps
in the 60s most of the week, highs only in the 50s are expected
for Fri through Sunday. Friday night lows will also be the coolest
with mid 30s expected across the entire area.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 602 PM CDT Sun May 3 2020
VFR conditions will prevail through the period. Lingering clouds
are about out of eastern Illinois, and skies will be clear until
high and mid level clouds arrive on Monday ahead of the next
system. Northwest winds early this evening will trend toward the
northeast after 06Z, and increase to around 10 knots by late
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SYNOPSIS...Geelhart
SHORT TERM...Auten
LONG TERM...Auten
AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Louisville KY
909 PM EDT Sun May 3 2020
.Forecast Update...
Issued at 908 PM EDT Sun May 3 2020
Went ahead and cancelled Severe Thunderstorm Watch #160 in
coordination with SPC/JKL/OHX across our SE CWA. Recent radar trends
have shown a steady decline in convective strength along with
warming IR cloud tops. Expect activity to continue pushing SE along
with the surface front over the next few hours, leading to a dry
rest of the overnight. Main concern will be patchy fog potential as
we approach dawn on Monday. Updated products with the watch removed
are already out.
Issued at 746 PM EDT Sun May 3 2020
Severe Thunderstorm Watch #160 was issued until 1100 PM EDT for our
far south and east CWA. The main concern was the northern fringes of
a persistent bowing MCS that worked across north central TN and had
potential to clip the Lake Cumberland counties. In addition,
convection showed a steadily increasing trend along the SW to NE
oriented cold front across east central KY. We seen some small hail,
brief heavy rainfall and gusty winds to 40 mph, but the main threats
will be south and east of the CWA for the remainder of the evening.
Will be looking to drop the remainder of the watch counties over the
next hour or so.
We`ll clear out some remaining showers through the overnight, and
watch for some potential fog development in the wake of this system
toward the pre-dawn hours.
&&
.Mesoscale Update...
...Isolated Severe Threat in Southern KY...
A bowing QLCS is producing widespread severe wind across Middle TN,
including a 72 MPH gust at the Nashville International Airport. The
northern part of this bowing line is expected to skirt the KY/TN
border, with the more widespread severe threat remaining south of
the border.
In addition, a NE to SW oriented line of sub-severe convection has
developed along a southeastward moving cold front, now located from
Winchester to Bowling Green. Around 1000 J/kg is present south of
the boundary across south-central KY with a bullseye of around 1500
J/kg along the TN border. However, the more favorable DCAPE values
in excess of 800 J/kg are confined to a smaller area with steeper
low level lapse rates in the southeastern CWA. So most areas south
of the Bluegrass Parkway could see brief heavy rainfall, gusty winds
to around 40 mph, lightning, and possibly small hail. Any isolated
severe threat is confined to mainly along and south of the
Cumberland Parkway and east of Glasgow over the next 1-2 hours.
Damaging winds are the primary severe hazard. Brief torrential rain
could result in localized ponding/flooding.
&&
.Short Term...(This evening through Monday)
Issued at 235 PM EDT Sun May 3 2020
...Severe Storms Possible This Afternoon And Evening...
A stationary boundary across southern IL/IN/OH has started to drift
southward as a cold front over the last few hours. Surface
convergence along the front and outflow boundaries from recent
convection have helped spark of shower and storm development across
southern IN within the past couple of hours. This front will
continue to move southward this afternoon and serve as a focus for
convective development. Low level moisture should continue to pool
ahead of the frontal boundary, and with fairly modest mid-level
lapse rates, SBCAPE should climb into the 1500-2500 J/KG range. Deep
layer shear will support organized convection, and may even support
some supercellular structures. Straight line hodographs and fairly
weak low level shear will keep any tornado threat low today with
discrete convection.
In addition to the front, a fairly long-lived QLCS currently over
southeastern MO will likely hold together and move into western KY
and perhaps clip south-central KY late this afternoon. CAMs like the
HRRR indicate this MCS will maintain itself and remain fairly strong
by the time it arrives close to us, though recent radar trends
suggest it is diving more to the south and east then what CAM
guidance predicts. Should radar trends hold, it`s possible it could
miss our CWA completely. In any case, strong, damaging straight-line
winds would be the most likely threat with that QLCS, though an
isolated spin-up tornado in bowing segments of the line would be
possible as 0-3km shear vectors support some tornado potential.
The only "fly in the ointment" with today`s convection are sub-par
temperatures near the 700mb level, which may hamper overall updraft
strength and storm severity. However, given that surface
temperatures have climbed well into the mid and upper 70s ahead of
the front with dewpoints in the mid 60s, surface parcels should be
able to overcome the warmer temperatures aloft to promote strong to
severe storm potential.
Convection will steadily decline in coverage from northwest to
southeast tonight as drier air works in behind the front. We should
see clearing across most of southern IN and central KY toward dawn
and could result in some patchy fog in the usual fog prone areas
with light winds in place. Most of tomorrow is shaping up to be dry,
but clouds will be on the increase late tomorrow afternoon ahead of
our next system.
.Long Term...(Monday night through Sunday)
Issued at 230 PM EST Sun May 3 2020
...Unsettled with temperatures turning cooler mid week...
Monday Night - Tuesday...
Zonal flow aloft will prevail over our region during this stretch,
with a notable mid and upper level impulse oriented E-W over the
area. A surface low is expected to move out of the mid Mississippi
River Valley and into southern KY late Monday night into Tuesday,
with the best low level jet response across the southern half of KY.
Categorical pops with some chance of thunder continue to be
reasonable across the southern and central part of KY during that
stretch. At this point, most of the instability should be elevated,
however there may be a chance for some meager surface based
instability just ahead of the surface low across south central KY on
Tuesday morning. If a small instability axis develops ahead of the
surface low Tuesday morning, there may be an eventual Marginal
threat for severe. Something to watch. Total rainfall through this
time should be between .75" and 1" across our south, with amounts
likely less than a half an inch across northern KY and southern IN.
Tuesday highs should be in the 60s under heavy cloud cover.
Tuesday Night - Wednesday...
General troughing will hold over the eastern 1/3 of the CONUS
through mid week. Several chances for rain showers will exist with
each individual disturbance embedded in the parent rough. Although
it won`t be a washout. Highs will stay in the 60s with lows in the
40s.
Wednesday Night - Thursday...
NW flow aloft holds over the area at this time, with uncertainty
with regard to individual shortwaves moving through the upper flow.
There is a chance we see a brief dry spell here, with surface high
pressure in place, but too much model uncertainty to be too
confident. Lows in the 40s with highs in the 60s should be a
continuing trend.
Thursday Night - Friday...
An anomalous upper low will (~520 500 mb Heights) will settle
somewhere near the Great Lakes by the end of the work week and looks
to potentially phase with a weaker shortwave diving into our region
from the NW CONUS. This should bring the next solid chance of rain
to the area, followed by a strong cold front. Depending on timing of
the front highs will only be in the 50s/60s Friday.
Friday Night - Sunday...
The strong cold front passes by Friday night, bringing in high
pressure at the surface and what appears to be drier NW flow aloft.
As a result, look for a dry weekend with highs only in the upper 50s
and low 60s and lows in the 30s. Frost Advisories seem like a
possibility Friday or Saturday night.
&&
.Aviation...(00Z TAF Issuance)
Issued at 735 PM EDT Sun May 3 2020
Thunderstorm activity is now pushing south and east of BWG/LEX, but
may still hang onto a few lingering showers or perhaps a rumble of
thunder for the next couple of hours. In addition, ceilings will
flirt with VFR/MVFR, but think VFR mostly prevails. Surface winds
are going NNW to NNE behind the front, and expect this to prevail
for much of the overnight with a gradually lifting 4-8 K foot mid
deck. Skies should go clear toward dawn, with a light NNE surface
wind by that time. Can`t rule out some fog, but models don`t seem
to be hitting it all that hard at this time, so will continue to
monitor.
Expect a VFR and dry Monday with a light NE surface wind. Some VFR
cloud ceilings arrive toward then end of this TAF cycle, and another
round of rain arrives past Monday night.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Mesoscale...EBW
Update...BJS
Short Term...DM
Long Term...BJS
Aviation...BJS
Area Forecast Discussion
National Weather Service Marquette MI
812 PM EDT Sun May 3 2020
.SHORT TERM...(This evening through Monday)
Issued at 421 PM EDT SUN MAY 3 2020
Water vapor imagery and RAP analysis show a shortwave trof moving
across Upper MI/Lake Superior. At the sfc, a cold front has recently
pushed s of Upper MI. Secondary trof is pushing s and is roughly
halfway across Lake Superior. As expected, abundant cloud cover
quickly developed across much of the fcst area this morning, and
conditions have been much cooler than yesterday with 40s dominating
the day across the w and n. Some locations have fallen into the 30s.
However, far s central Upper MI has enjoyed a mostly sunny mild day.
Some sprinkles and -shra have occurred over n central Upper MI
today. A few -shsn have also been noted in the Keweenaw per a
spotter report and a webcam in the high terrain of Keweenaw County.
Meanwhile, temp at Menominee was 65F.
Weakening secondary sfc trof will push s across the area over the
next several hrs. Expect some light pcpn, -shra/-shsn or sprinkles
and flurries, to occur in the vcnty of this trof into the evening
hrs from the Keweenaw into the n central and eastern fcst area.
Drying will then bring an end to the pcpn late evening into the
early part of the overnight. With extensive stratocu, not all
diurnally generated, noted upstream in ne MN into northern Ontario,
clouds may be slow to clear out during the night, particularly where
northerly winds upslope. Expect min temps in the mid 20s to lwr 30s.
On Mon, some stratocu may briefly linger in the morning over
portions of central Upper MI. Otherwise, expect a sunny day though
some high clouds will begin to increase into the western fcst area
during the aftn. Sfc high pres will be centered over northern
Ontario, but as the land heats up during the day, a secondary center
will form over central Lake Superior. Result will be especially cool
conditions along Lake Superior. The cool marine influence will
spread much farther inland over the n central and eastern fcst area
due to long fetch and low-level winds perpendicular to the land in
that area as opposed to a wind orientation that is more parallel to
the land along the shoreline of western Upper MI. Expect highs in
the 40s lakeside w, across the n central and eastern fcst area.
Temps may not reach 40F lakeside n central and e. Temps will rise to
the low/mid 50s interior w into the s central. Very dry air mass
aloft will be tapped by deepening mixed layer. Incorporated some of
the this mix down potential to drop dwpts to as low as the lwr to
middle teens. Result will be RH bottoming out in the 20-30pct range,
lowest interior w half. Fortunately, winds will be lighter on Mon to
help lessen fire wx concerns over what they could be.
.LONG TERM...(Monday night through Sunday)
Issued at 328 PM EDT SUN MAY 3 2020
Aloft at 500mb, overall pattern continues to show an amplifying
ridge over much of western North America keeping upper level
northwest flow across the region as downstream troughing digs into
the region toward the end of the week. Overall, this will mean an
extended period of below normal temperatures for Upper Michigan.
Weakening high pressure sliding into eastern Ontario will keep the
pattern dry Monday night into Tuesday. A shortwave moving through
the northern Plains Tuesday will track southeast into Wisconsin,
increasing high cloud cover Monday night and giving the region a
chance of some rain with some snow flakes mixed in. Models continue
to trend dryer and dryer and highlight a healthy low layer of dry
air below the high clouds through the day Tuesday, with deep mixing
into this dry layer. Because of this, I`m skeptical on any
accumulation and have lowered PoPs to reflect this thinking. Despite
the deep mixing, gusty winds are not expected. Lows Monday night
will largely depend on how fast cloud cover filters in. If cloud
cover holds off long enough, portions of the central and east could
drop into the low to mid 20s while the south and far west hover near
30. Highs Tuesday will reach the 40s by the lakeshores and reach the
50s further inland.
High pressure building across the region following this low`s exit
will keep the region mostly dry Wednesday and Thursday. A vigorous
shortwave diving south on Thursday looks to stay mainly east of the
CWA but some precip grazing the eastern counties looks possible
right now. Overall, this shortwave will usher in cooler temps.
Thursday highs into the weekend will be in the 40s for most, with
some high 30s possible Friday. Overnight lows in the 20s in the
interior and near 30 by the lakeshores should be expected.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 804 PM EDT SUN MAY 3 2020
Sfc trough and associated low-level moisture dropping s across
the area have resulted in scattered snow and rain showers at KCMX
and KSAW late afternoon/evening with bkn to ovc stratocu mainly
in the MVFR range. KIWD has escaped shower activity this evening
and the cigs there are at VFR. With drier air arriving tonight
and Mon, MVFR cigs will scatter out later tonight at KCMX and KSAW
with VFR conditions then prevailing thru Mon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 421 PM EDT SUN MAY 3 2020
High pres will build across northern Ontario tonight and Mon. This
will favor stronger winds, gusts to 20-25kt, over the e half of Lake
Superior tonight. Some gusts to 30kt will be possible into the
evening. Over western Lake Superior, expect winds under 20kt.
Secondary sfc high pres center will form over central Lake Superior
Mon aftn. So, stronger winds, gusts around 20kt, will become focused
w of the Apostles and toward Whitefish Bay on Mon. Relatively weak
pres gradient should keep winds under 20kt Tue/Wed. Unseasonably
cold air mass arriving late week will likely result in stronger
winds Thu/Fri, especially across central and eastern Lake Superior.
Gusts up to 30kt may be possible at times.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...JP
AVIATION...Voss
MARINE...Rolfson
Area Forecast Discussion
National Weather Service New York NY
1023 PM EDT Sun May 3 2020
.SYNOPSIS...
A cold front approaches this evening and passes east overnight.
Low pressure along the front deepens offshore Monday. High
pressure builds to the west through Monday night and then over
the region Tuesday. Low pressure will pass to the south, then
southeast of the region mid week. A cold front approaches moves
across the region late Friday into the start of the weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Beginning time of the onset of light rain delayed a couple of
hours as area of precipitation with a weak shortwave was moving
through Maryland and into Delaware at 02Z. Then as the shortwave
interacts with an approaching cold front after 04Z precipitation
will begin to become more widespread across the southern zones.
Clouds will overspread the area as the cold front and 500 mb
shortwave energy approaches into the overnight. A complex of
showers is likely to develop ahead of the shortwave, but model
consensus continues to track this activity south of Long Island.
There are still some solutions that take showers near or over
portions of Long Island and just south of Connecticut overnight
with the HRRR being the most aggressive. A slight to chance PoP
is forecast across these locations.
The wave pushes south and east towards day break with any showers
ending. Lows tonight will be in the upper 40s to lower and middle
50s, warmest in the NYC metro.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Upper trough axis moves across New England on Monday with
deepening low pressure offshore. High pressure will also begin
building to our west. Shortwave energy within the trough pivots
across the region late morning into the early afternoon. This
will bring a slight increase in clouds from a partly cloudy
start. Have also included a slight chance for a shower across
the NW interior, but otherwise dry conditions prevail in the
afternoon.
The pressure gradient between the offshore low and building
high pressure to the west will bring gusty NW winds, especially
in the afternoon. Wind gusts 25 to 30 mph are expected.
Temperatures will be much cooler than this past weekend,
generally in the lower to middle 60s.
The upper trough and offshore low move further away from the
coast Monday night as the surface high continues to build from
the west. The gradient relaxes somewhat through the night, but
currently do not think the winds decouple completely for ideal
radiational cooling conditions. However, cold advection will
continue allowing temperatures to fall well below average in the
30s inland to the low 40s near the coast. If the winds drop off
quicker across the interior, then some frost would possible
with temperatures falling into the middle 30s.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
High pressure builds into the region Tuesday with temperatures
around 5 degrees below normal.
Low pressure is then expected to pass south of the region
Tuesday night and Wednesday, however as it moves off the coast,
an upper level trough will move over the region, steering the
surface low northward, so it passes southeast of Montauk Point.
The question is just how far offshore this low will pass and how
deep the low strengthens. Expect most of Wednesday to remain
dry, however will bump up POPs to at least chance Wednesday
night and Thursday, as the upper level low passes over the area
and the offshore surface low passes closest to the region.
Expect a chance of showers through this period.
Very weak ridging builds over the area Thursday night, before
sliding east on Friday. This will allow a cold front to approach
Friday morning and move across the area Friday afternoon and
evening. Aloft, an upper level low moves over the region, with a
shortwave moving across the region on Saturday. This shortwave
could result in additional showers for at least the first half
of the weekend.
Temperatures through the long term will remain below normal for
this time of year.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
A cold front slowly approaches, and moves across the region
overnight. A gusty northwest flow results Monday as low pressure
moves slowly through the Canadian Maritime.
VFR through the period. There is a low chance of showers
overnight mainly at KJFK,KISP, and KGON.
S to SW winds less than 10 kt shift to the west and northwest
with the approach and passage of a cold front overnight into
early Monday. Monday morning NW winds, around 310 magnetic,
increase to around 15 kt with gusts to around 20 kt. In the
afternoon gusty NW winds increase 15 to 20 kt, gusting 20 to 30
kt. Gusts continue into the early evening Monday, then diminish.
.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.Monday night...VFR. NW winds G20-30kt early in the evening.
.Tuesday-Wednesday...VFR.
.Wednesday night and Thursday...Mainly VFR. Showers with
periods of MVFR possible.
.Friday...Mainly VFR, brief MVFR conditions in showers possible.
&&
.MARINE...
A cold front moves across the waters overnight into early Monday
morning. A wave of low pressure will move along this front and
then deepen offshore on Monday. Winds and seas will remain below
SCA levels tonight into Monday morning.
The pressure gradient increases between the offshore low and
building high to the west. This will lead to wind gusts on all
waters increasing to 25-30 kt in the afternoon and evening. The
gusts should weaken below SCA levels on the non-ocean waters
overnight, but likely remain around 25 kt on the ocean through
Tuesday morning. Ocean seas will also build to around 5 ft Monday
night. An SCA has been issued on the ocean 18z Monday to 10z Tuesday
and on the non-ocean waters 18z Monday to 06z Tuesday.
High pressure builds into the region Tuesday with a storm passing
well south of the waters Tuesday night into Wednesday. Other than
some shifting winds, the storm still looks far enough south to
prevent winds and seas from increasing to advisory criteria. High
pressure builds back over the waters Thursday into Friday. Winds and
or seas may build to advisory level behind the cold front on Friday
evening.
&&
.HYDROLOGY...
No hydrologic impacts are expected through Friday.
&&
.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is undergoing
its final stages of testing, and is operating at full power.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 2 PM Monday to 2 AM EDT Tuesday for
ANZ330-335-338-340-345.
Small Craft Advisory from 2 PM Monday to 6 AM EDT Tuesday for
ANZ350-353-355.
&&
$$
Area Forecast Discussion
National Weather Service Pueblo CO
616 PM MDT Sun May 3 2020
.SHORT TERM...(This evening through Monday)
Issued at 329 PM MDT Sun May 3 2020
Currently...Skies mostly sunny across the region. A dryline surge
was starting to push east from the mtns at K4VI and KTAD are gusting
from the SW while areas on the plains farther east and north still
have S to SE sfc winds. RH values were also starting to drop behind
the dryline. In the SLV, Red Flag conditions were occurring due to
the gusty winds and very low humidity values.
Just north of the CWA, TSRA were noted forming over the Palmer
Divide. A few Q were also noted along the dryline.
Rest of Today into Tonight...
Main concern will be isolated TSRA potential over N El Paso and N
Kiowa counties late this afternoon and evening. Guidance has been
hinting on and off that we may see some isolated thunder these
regions during this time period. HRRR has also, on occasion, shown
an isolate storm over the far eastern plains, and given the bulge
pushing out. this cant be ruled out. Otherwise, the fcst area will
see mostly clear skies tonight. The only exception to this may be
the far eastern plains where some low clouds may build back west
later tonight.
Per SPC mesoanalysis page, mixed CAPE values pushing 500 J/Kg and 30-
40 knts of shear was noted, and even the Supercell Composite index
was showing some low numbers out east, so cant rule out an isolated
marginally svr storm during the next several hours.
As for the Red Flag, the San Luis Valley (SLV), southern mtns and
southern I-25 corridor will see critical fire weather conditions
into the evening hours due to the gusty SW winds and low RH values.
A rather strong cool front will push south across the Palmer Divide
around midnight, and across the rest of the plains during the early
morning hours of Monday. Gustiest winds will likely remain north of
and along US-50 during the nighttime hours.
Tomorrow...
Breezy conditions likely tomorrow in the morning most over the
plains, with winds slackening up over the I-25 corridor by later in
the afternoon, but will keep up over the far eastern plains.
Critical fire weather conditions are not expected tomorrow over the
plains as the combination of RH and winds should not exceed critical
values. However, it will be windy over the far eastern plains (but
RH values should be above 15%) while over the I-25 corridor RH
values will be critical, but winds should be relatively weak.
Over the mtns, a few areas, especially the northern SLV, will reach
critical values, but this is over a relatively small area, so no
fire weather highlights have been issued for tomorrow.
Cant rule out an isolated tsra over the Pikes Peak region tomorrow
and possibly down across the Wet Mtns, however nearly all areas will
remain dry with temps about 3-5F cooler than todays max temps.
.LONG TERM...(Monday night through Sunday)
Issued at 329 PM MDT Sun May 3 2020
Monday night-Tuesday night...Moderate westerly flow aloft continues
across the region with another embedded short wave translating across
the Rockies Monday night. The passing wave is progged to send another
cold front across the eastern plains Monday night, with the front
banked up across the lower slopes of the southeast mountains by
early Tuesday morning. With moisture pooling along and behind this
front, can`t totally rule out a few possible showers across the
southeast plains Monday night and early Tuesday morning. With that
said, it seems the latest NAM nam solution is overdone with its
convection and have cut back on NBM pops and qpf across the plains
through Thursday morning. At any rate, Tuesday looks to start out
cloudy across the plains, with isolated to scattered showers and
a few possible storms, developing over and near the higher terrain
west of the I-25 Corridor Tuesday afternoon and early evening.
High temperatures across the plains on Tuesday will be cooler than
Monday, though will still be around seasonal levels, in the 60s
to lower 70s. Highs further west will be near Monday`s readings,
in the mid 60s to lower 70s across the high mountain valleys, with
mainly 50s and 60s across the higher terrain. While there will
continue to be a few areas of critical fire weather conditions
across the high mountain valleys through this period, current
forecast does not indicate widespread enough conditions to issue
any fire weather highlights at this time.
Wednesday-Thursday...Short wave upper level ridging is progged across
the area Wednesday, with more energy progged to dig down the back side
of the ridge across the Plains on Thursday. This keeps warm and mainly
dry conditions across the area through this period, with a stronger
cold front progged to dive across the eastern Plains Thursday afternoon
and evening, bringing chances of precipitation across the plains
Thursday night. Temperatures warm back to above seasonal levels
areawide, with the potential for more widespread critical fire weather
conditions on Thursday.
Friday-Sunday...Moderate northwest flow aloft continues to be progged
across the region, as a broad upper trough carves out across the
central Conus and upper level ridging redevelops across the Desert
Southwest through the Intermountain West. Latest models continue to
differ on timing and location of minor embedded waves translating
across the region through the weekend, and again stayed with current
NBM pops, which brings chances for showers over and near the higher
terrain each afternoon. Temperatures through the period look to cool to
near seasonal levels, most notably across the plains.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 606 PM MDT Sun May 3 2020
VFR and dry conditions across the TAF sites this period. Latest
radar imagery is depicting some isolated shower and thunderstorm
development just to the north of COS at this time, however, this
development is expected to stay to the north. There could be a
stray shower that moves around COS early this evening, but impacts
are not expected and have left out any mention of precip. Winds
will generally be from the southwest to west this period across
ALS, but for COS and PUB expect some varying wind direction
beginning as soon as this early. Surface trough/front expected to
swing through and allow current south southeast winds to quickly
shift to a northerly direction while remaining gusty. There is
some potential for winds/gusts to diminish later tonight into
early Monday morning, but it is appearing more probable for
another increase in speeds and have trended the forecast this way.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT this evening for COZ224-225-229-
230.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MW
AVIATION...RODRIGUEZ