Flooding Continues in Arenac County Along the Rifle River

                        

229

ACUS01 KWNS 171622

SWODY1

SPC AC 171621



Day 1 Convective Outlook

NWS Storm Prediction Center Norman OK

1121 AM CDT Wed Jul 17 2024



Valid 171630Z - 181200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND

EVENING ACROSS PARTS OF THE NORTHEAST STATES AND MID-ATLANTIC

REGION...AND OVER NORTHEAST COLORADO....



...SUMMARY...

Damaging thunderstorm gusts appear most likely and concentrated

today over parts of the Mid-Atlantic into central/southern New

England. Other severe storms may affect parts of the central High

Plains.



...Northeast States...

Visible satellite imagery shows mostly clear skies from northern VA

northeastward into eastern PA/southeast NY and much of New England.

This corridor is quite moist with dewpoints in the upper 60s to 70s,

and should become moderately unstable this afternoon with pockets of

MLCAPE of 1000-1500 J/kg.  A consensus of 12z models show scattered

thunderstorm development across the region - especially focused from

eastern PA into southeast NY.  Broad southwesterly mid-level winds

in the 35-45 knot range will help to organize storms and support

multiple rounds of potentially severe wind gusts.  Storms will track

across southern New England and into eastern MA/NH and southern ME

by evening.  Coverage of convection farther south across NJ/DE/MD/VA

is expected to be a little lower, but will still be capable of

locally damaging wind gusts through the afternoon and early evening.



...High Plains...

Similar to yesterday, afternoon high-based thunderstorms are

expected to build eastward off the foothills of the CO Front Range.

Isolated strong/severe storms are possible with locally damaging

gusts and some hail the main risks.  Most 12z HREF members show a

cluster of more organized and intense storms building off of the

Palmer Ridge into northeast CO.  The potential for more organized

outflow and greater coverage of intense storms has prompted the

addition of a small SLGT.



...TX...

A large cloud shield associated with remnant convection is present

today across parts of OK/AR and central TX.  Strong heating to the

south of these clouds and near remnant outflow boundaries will

promote afternoon thunderstorm development.  Hot/humid conditions

and steep low-level lapse rates could result in gusty/damaging wind

in the strongest cells.



..Hart/Halbert/Squitieri.. 07/17/2024



$$






                

                        

872

ACUS02 KWNS 171731

SWODY2

SPC AC 171729



Day 2 Convective Outlook

NWS Storm Prediction Center Norman OK

1229 PM CDT Wed Jul 17 2024



Valid 181200Z - 191200Z



...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST

VIRGINIA AN PARTS OF THE CAROLINAS...AND IN THE CENTRAL/SOUTHERN

HIGH PLAINS...



...SUMMARY...

Isolated strong to severe thunderstorms are possible Thursday

afternoon across the central and southern High Plains as well as

from the Virginia Tidewater across the eastern Carolinas.



...Synopsis...

An expansive upper-level ridge will be present across much of the

West into the Plains on Thursday. An upper trough will depart the

Northeast by the late afternoon/evening. A shortwave trough will

slide over the upper ridge in the northern Rockies. An MCV will

likely track eastward from the ArkLaMiss into Alabama. At the

surface, a cold front will be situated from the Mid-Atlantic into

the western Carolinas with a westward extension into the Mid-South

and southern Plains. This front will be more diffuse with westward

extent. Surface high pressure will be the predominant feature in the

Midwest and Ohio Valley with a weak surface low developing in

Montana ahead of the shortwave trough.



...Southeast Virginia into parts of the Carolinas...

Scattered to numerous storms are expected to develop along the cold

front by the afternoon. There is some uncertainty as to the degree

of destabilization that will occur. This is in part due to some

potential convection developing along the sea breeze with

outflow/cloud debris affecting storms that develop farther west

along the front. The airmass will be quite moist, however, and even

broken cloud cover will support 2000-3000 J/kg MLCAPE (larger values

being more probable with southern extent). With modest mid-level

flow along the southern periphery of the upper trough, effective

shear of 30-40 kts will support primarily multicells/linear clusters

with a few marginal supercells. Mid-level lapse rates will be weak

making large hail potential low. The primary hazard will be damaging

winds. Depending on the degree of destabilization, there could be

potential for a corridor of greater damaging wind potential should a

more organized cluster develop.



...Central/southern High Plains...

Very modest moisture return is expected to occur along the western

flank of the surface high. Forcing for ascent will be weak, but

widely scattered to possibly scattered convection will develop along

the terrain and within the weak lee trough. Storm coverage with

eastern extent is less certain, but outflow boundaries may provide a

focus for development. There will be some enhanced mid-level winds

across the region promoting 30-40 kts of effective shear. Moisture

is a bit uncertain, with some guidance showing dewpoints mixing into

the mid/upper 40s to perhaps low 50s F, but a few isolated cells and

multicell clusters could produce severe winds and large hail.



...Northwest/north-central Montana...

The shortwave trough will be weakening with time, but will be

well-timed with afternoon heating. Storms are possible within the

terrain and within a weak surface trough. The main uncertainty will

be low-level moisture. A storm or two could produce a strong wind

gust and small hail, but confidence is too low for unconditional

severe probabilities.



..Wendt.. 07/17/2024



$$






                

                        

676

NWUS53 KAPX 160451

LSRAPX



Preliminary Local Storm Report

National Weather Service Gaylord MI

1251 AM EDT Tue Jul 16 2024



..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...

..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....

            ..REMARKS..



1128 PM     Tstm Wnd Dmg     2 NE Harbor Springs     45.46N 84.95W

07/15/2024                   Emmet              MI   Trained Spotter



            Power outages reported. Time estimated by

            radar.





&&



$$



HAD








                

                        

849

FXUS63 KAPX 171742

AFDAPX



Area Forecast Discussion

National Weather Service Gaylord MI

Issued by National Weather Service Chicago IL

142 PM EDT Wed Jul 17 2024



.KEY MESSAGES...



- Chances for scattered showers and isolated storms today



- Cool Thursday; warmer Friday through early next week.



&&



.SHORT TERM /THROUGH THURSDAY NIGHT/...

Issued at 317 AM EDT Wed Jul 17 2024



     Increasing chances of showers and thunderstorms today...



High Impact Weather Potential...Small chance of non-severe

thunderstorms today.



Closed upper low is poised over Ontario early this morning...with a

sharp upper level trough axis extending thru the Arrowhead of

Minnesota. Weak surface reflection is positioned just ahead of these

features...with the surface low now along the Ontario/Quebec border

and a cold front extending from the surface low back thru Lake

Superior into Central Minnesota. A few light showers are already

trying to pop across our SW CWA early this morning in response to

strengthening cyclonic flow and increasing low level moisture as the

above outline features approach.



Pronounced upper level trough axis will swing southeastward thru the

Western Great Lakes region today...reaching our far western CWA by

around midday and then clearing our CWA by around 00Z this evening.

Continued strengthening of cyclonic flow via this unseasonably deep

trough axis combined with increasing synoptic moisture and the

arrival of significantly cooler air aloft during peak diurnal

heating/instability will kick off scattered showers and isold

thunderstorms today into early evening. Instability will be

limited...generally AOB 500 J/kg...throughout the day which will be

enough to generate a few isold storms. But expect these storms will

remain sub-severe given lake of shear to organize convection. Temps

will be noticeably cooler today with afternoon highs ranging from

the upper 60s and lower 70s across the NW two-thirds of our CWA to

the mid to upper 70s from Apn southward to Saginaw Bay.



All precip chances will come to an end by around 00Z this evening as

the trough axis slides SE of our CWA and daytime instability wanes

as we approach sunset. Expect a cool mid July night across our

Northwoods with overnight lows dropping into the upper 40s and lower

50s.



&&



.LONG TERM /FRIDAY THROUGH TUESDAY/...

Issued at 317 AM EDT Wed Jul 17 2024



PATTERN SYNOPSIS/FORECAST:



Troughing will exit the forecast area Thursday into Friday, as

ridging/ pressure rises upstream track towards the area. Surface

high pressure will build overhead across the Northern Woods for the

second half of the week, making for less active weather. Uncertainty

then arises around shower/ storm chances at the beginning of next

week as an advertised shortwave trough is expected to influence the

region.



FORECAST DETAILS:



Surface high pressure will track overhead for the weekend with quiet

weather expected as a result. Temperatures will continue to be

cooler for Thursday with daytime highs expected to be in the low to

mid 70s, and overnight lows dipping well into the 40s across

interior areas Thursday night with calm winds and clear skies. More

seasonable temperatures make their return for Friday with highs in

the low 80s, which are anticipated through early next week. For

Saturday, a slight chance for some scattered showers will be

possible as lower heights work into northern Michigan. Looking at

Monday/ Tuesday next week, chances for showers/ thunderstorms exist

with guidance hinting at a shortwave trough influencing the forecast

area. However, consensus on the details of the aforementioned

feature have yet to be determined. Stay tuned as we continue to

analyze and fine tune these details!



&&



.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...

Issued at 142 PM EDT Wed Jul 17 2024



Forecast concerns for the terminals..



- Scattered showers and isolated thunderstorms this afternoon



- Periods of MVFR ceilings this afternoon and evening



An upper-level disturbance continues to pivot across northern

Michigan this afternoon which has allowed scattered showers and

a few thunderstorms to materialize. Forecast soundings continue

to show modest instability in place which should keep the

coverage of thunderstorms on the lower side for the rest of the

afternoon. Therefore, have decided to maintain just VCSH

mentions in the TAFs but did extend a TEMPO for thunder at KAPN

until 19z to account for the developing showers/storms west of

the terminal. Showers and any storms will wane this evening as

instability subsides leaving dry conditions for the rest of the

forecast period.



Otherwise, SCT to BKN VFR clouds are expected to persist through

the majority of the period. However, pockets of MVFR ceilings

have been observed across the Upper Peninsula and along the

Lake Michigan shore of northern Lower Michigan. While these MVFR

ceilings should be short lived if they make it to the

terminals, the potential for 2000 to 3000 ft clouds is expected

to linger through the evening.



As for winds, breezy northwest winds will persist through 00z

this evening with gusts in the lower 20 kt range. Wind speeds

will subside into the 5 to 10 kt range this evening and remain

as such through the rest of the period with directions out of

the north-northwest.



Yack



&&



.APX WATCHES/WARNINGS/ADVISORIES...

MI...None.

MARINE...Small Craft Advisory until 2 AM EDT Thursday for LHZ345-347-

     348.

     Small Craft Advisory until 2 AM EDT Thursday for LMZ323-341-

     342-344-345.



&&



$$



SHORT TERM...

LONG TERM...

AVIATION...






                

                        

324

ACUS11 KWNS 171627

SWOMCD

SPC MCD 171627

NHZ000-MAZ000-VTZ000-CTZ000-NYZ000-NJZ000-PAZ000-DEZ000-MDZ000-171830-



Mesoscale Discussion 1666

NWS Storm Prediction Center Norman OK

1127 AM CDT Wed Jul 17 2024



Areas affected...Eastern PA/northern NJ into western New England



Concerning...Severe potential...Watch likely



Valid 171627Z - 171830Z



Probability of Watch Issuance...80 percent



SUMMARY...The damaging-wind threat will increase this afternoon. One

or more watches will likely be needed.



DISCUSSION...Relatively strong heating is underway from parts of the

Mid Atlantic into western New England, to the east of an extensive

cloud shield that is moving eastward across western/central NY/PA

and WV. A seasonably deep upper-level trough will move eastward

across the lower Great Lakes and Northeast through the day, while an

MCV embedded in the larger-scale trough will move from WV toward the

Mid Atlantic. Cumulus is gradually building from east-central PA

into southeast NY, and a general increasing in storm development and

coverage is expected with time this afternoon.



Midlevel lapse rates are weak (as noted on regional 12Z soundings),

but continued heating will support MLCAPE increasing above 1000 J/kg

with time. Modestly enhanced midlevel flow will support 30-40 kt of

effective shear, sufficient for some storm organization. Multiple

storm clusters and possibly a couple of supercells may evolve with

time, with steepening low-level lapse rates supporting a primary

threat of damaging wind. Some threat for isolated hail and/or a

brief tornado is also possible if any supercells can be sustained.

One or more watches will likely be needed this afternoon to cover

the damaging-wind threat.



..Dean/Hart.. 07/17/2024



...Please see www.spc.noaa.gov for graphic product...



ATTN...WFO...GYX...BOX...BTV...OKX...ALY...PHI...BGM...CTP...

LWX...



LAT...LON   40317389 39737510 39527769 39867743 41267620 42887433

            43587327 43697258 43467206 42067273 40317389