Absolute Vorticity

Mike must have reclaimed his dome - picked up 1.05" overnight.

I've had a few sprinkles here again. Radar getting active as expected to our West and NW.

Been in and out of light showers here. Just a hundredth or two so far. 76 for my high so far, currently sitting at 74 / 70. MD issued for a watch not likely to be issued because there are just too many clouds and showers out there for stronger cells to get going for us.

https://www.spc.noaa.gov/products/md/md1128.html

Now the SPC did extend the slight risk area into Cincinnati now. 15% wind and hail for the main hazards.

https://www.spc.noaa.gov/products/outlook/day1otlk.html

Despite the clouds... we do have CAPE of 2000-2500 J/kg for the area. 30 knots of bulk shear but very poor lapse rates. I like the marginal risk call from earlier to be honest but we'll keep an eye on things just in case. We do have a boundary in the region from IND to Cincy and into NKY as well... I-74 corridor if you will so storms will continue to pop and ride SE along that boundary for the rest of the day into this evening.


We shall wait and see where the MCS gets going later today but my guess is SD and it'll drop SE along that boundary, wherever it happens to be for late tonight / Mon morning time frame. Could be us or just to our SW like Louisville. That could be why the SPC bumped it up to a slight risk I guess.

Clouds are trying to thin some to our West... we'll see if those trends continue for our local area.

79 degrees here with a dew of 72. Seeing a touch of sun breaking thru the clouds now. A watch is not likely to be issued for Ohio.

https://www.spc.noaa.gov/products/md/md1131.html


From the boys thru Mon night:

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
An embedded disturbance will continue to move southeast to the
middle Ohio River Valley this evening. Meanwhile, a weak front
to our north will settle into the region tonight where it will
stall. The combination of these two features will result in the
likelihood of showers and storms across the northern/central
zones, and a chance of showers and storms over the southern
zones. Moderate instability (1000-1500 J/kg MLCAPE) and low end
moderate deep effective shear, will continue to pose an
isolated severe thunderstorm threat. Gusty to damaging winds
are the primary threat. The threat of severe storms should wane
later this evening as the disturbance moves away. For the
overnight hours, it appears the chance of showers/storms will
become more confined to locations along and south of the Ohio
River. Lows will range between 65 and 70.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
An anomalous mid level ridge to our southwest will begin to
build northeast into the Ohio Valley Monday into Monday night.
As this occurs, a warm front will merge with aforementioned
stall out boundary, pivoting north/northeast toward the southern
Great Lakes Monday night.

On Monday, uncertainty abounds in terms of convective evolution
and coverage during the day. Some models try to bring an MCV
from Missouri into the middle Ohio Valley where it tries to
develop into an MCS across parts of Kentucky. Confidence is low,
so at this point, a broad brush forecast with chance PoPs
associated with the advancing warm front has been employed.
Given increasing strong to extreme instability with dewpoints
pushing into the lower to mid 70s, along with continued ample
deep layered shear, thunderstorms may become severe with
damaging winds and large hail. Can not rule out isolated heavy
rainfall with pwats around 2 inches. Monday will see the
beginning of a period of very hot and humid weather. Have highs
ranging from the upper 80s northeast to the lower 90s along and
south of the Ohio River. With aforementioned dewpoints, this
will result in heat index values between 95 and 100, highest
over the south. This is just tickling Head Advisory criteria.
Will continue to mention this in the HWO product.

As we head into late Monday into Monday night, models still
show uncertainty in terms how a convectively enhanced
disturbance will propogate from the upper Mississippi River
Valley to the Great Lakes. There has been a general trend in the
models to move the feature a little bit farther north and east
from previous runs. This has been reflected in the latest SPC
SWODY2 Outlook, which now has our northern zones (west central
Ohio into central Ohio) still under a risk for severe storms.
Again, given the strong to extreme instability feeding into this
feature, we will have to monitor later model guidance. In fact,
some models develop a bowing like structure which would result
in a more widespread wind damage threat. Large hail will also be
a threat. Lastly, can not rule out isolated tornadoes given
veering profiles near the warm frontal boundary. These threats
continue in the HWO for the mentioned area. It will be warm and
muggy Monday night with lows only in the lower to mid 70s.

Couple of big storms around Sidney, OH right now which will slide SE and impact our NE counties. Meanwhile off to the West, scattered showers are developing over S. IN just W of I-65. A few scattered showers and storms are possible this evening but warm, and humid is the bigger story attm.

Big MCS starting to form in Western SD now so we'll keep an eye on it for tomorrow and any outflow boundaries it sends in the OV's direction. Severe wx tomorrow once again is uncertain and conditional. Mon night things may get nasty over S Michigan and Northern IN, OH with a possible derecho / MCS.

The fuel for storms is a chart Topper for tomorrow. I've seen anywhere from 5000 to as much as 7000 cape , mostly centering on central Ohio. But the whole corridor from Indy to cincy and of course northward has that derecho potential.

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM EDT
FOR SOUTHWESTERN CHAMPAIGN AND NORTHWESTERN CLARK COUNTIES...

At 722 PM EDT, a severe thunderstorm was located near New Carlisle,
moving southeast at 30 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Minor hail damage to vehicles is possible. Expect wind
damage to trees and power lines.

Locations impacted include...
Springfield, New Carlisle, Christiansburg, North Hampton, Tremont
City, Thackery, Westville, Terre Haute, Lawrenceville, Dialton and
Buck Creek State Park.

IND and LOU both have heat advisories issued for their Western counties for tomorrow. HI's are forecast to be in the 105-110 degree range.

Nice view of the anvil on this bad boy as I’m leaving work! Storm is around 50 miles away. Gotta love it!

My gauge picked up 1.10" from Sat night.

That's a gorgeous shot Trev! Just humid and nasty here.

tron777 wrote: ↑Sun Jun 12, 2022 8:10 pm That's a gorgeous shot Trev! Just humid and nasty here.

Thanks @Les! Tops on this thing were >50k feet! Impressive but not uncommon this time of year.

Trevor wrote: ↑Sun Jun 12, 2022 8:35 pm

tron777 wrote: ↑Sun Jun 12, 2022 8:10 pm That's a gorgeous shot Trev! Just humid and nasty here.

Thanks @Les! Tops on this thing were >50k feet! Impressive but not uncommon this time of year.

That would explain seeing it from that far away then... awesome!

We were seeing that storm on the way home from Versailles, KY. We could see it from across the river.

Here in Hyde Park we had another half inch of rain last night. That puts us at 3.85 inches since Monday morning. Very lush around here.

Looks like a potentially dangerous couple of days ahead. Severe storm potential today and possibly tonight for northern posters. Then the excessive heat and humidity for Tuesday and Wednesday.

Good Morning and here we go with the heat and humidity. I have been on the low end with temps over the next several days. Will that be a bust and I have been watching this ridge expand more to the northeast instead of north so that may be a bust for me but first need to see how later today plays out. No doubt the mcs looks to be rather strong later today but will the expanding ridge push the strongest part of the mcs further north and east. I see the NWS has a excessive heat watch out for Tuesday afternoon and evening as they expect heat index to be near 109 in some places. Not sure we get that high but anything over 100 will feel quite nasty.

tpweather wrote: ↑Mon Jun 13, 2022 7:51 am Good Morning and here we go with the heat and humidity. I have been on the low end with temps over the next several days. Will that be a bust and I have been watching this ridge expand more to the northeast instead of north so that may be a bust for me but first need to see how later today plays out. No doubt the mcs looks to be rather strong later today but will the expanding ridge push the strongest part of the mcs further north and east. I see the NWS has a excessive heat watch out for Tuesday afternoon and evening as they expect heat index to be near 109 in some places. Not sure we get that high but anything over 100 will feel quite nasty.

My yard is still pretty "gooshy", abnormally so. John Gumm posted over the weekend about temps in the 97 degree range, I said those have to be wrong, no way with the ground moisture around here that temps get that hot. I can see higher heat indices, because humidity will be a bear, but not temps as high as the models are spitting out to them. Guess we'll see....

SPC Day One outlook now with enhanced across northern Indiana and NW Ohio north of I-70. This is the most likely path of the potential derecho system later today/tonight.

There is also growing concern locally for a separate more rooted MCS system later this afternoon forming across Indiana and moving into SW Ohio/NKY around the 6-8 pm timeframe. Models are all over the place on this, however there will be extreme CAPE/DCAPE in the area so we need to watch this closely.

House of Cards wrote: ↑Mon Jun 13, 2022 8:27 am

tpweather wrote: ↑Mon Jun 13, 2022 7:51 am Good Morning and here we go with the heat and humidity. I have been on the low end with temps over the next several days. Will that be a bust and I have been watching this ridge expand more to the northeast instead of north so that may be a bust for me but first need to see how later today plays out. No doubt the mcs looks to be rather strong later today but will the expanding ridge push the strongest part of the mcs further north and east. I see the NWS has a excessive heat watch out for Tuesday afternoon and evening as they expect heat index to be near 109 in some places. Not sure we get that high but anything over 100 will feel quite nasty.

My yard is still pretty "gooshy", abnormally so. John Gumm posted over the weekend about temps in the 97 degree range, I said those have to be wrong, no way with the ground moisture around here that temps get that hot. I can see higher heat indices, because humidity will be a bear, but not temps as high as the models are spitting out to them. Guess we'll see....

Great Post and I have been in the 88-92 range with the lower end on days where we have a mcs. With the lush vegetation and add higher dew points clouds will form in that 12-2pm most days. So yes a quick run up in temps in the morning only to be halted in the early afternoon imo. Of course this is not even dealing with a MCS. The only way I see higher temps is if we get some drier air in the mid layers on Wednesday and this would lower the dew points and may help produce less cloud cover mid-day but again that is without a mcs in the next 36 hours. I know Paducah got to 95 yesterday so that was a quick uptick and that at least got my attention. One other thing is the trough in the mountain areas of the west and that has been somewhat deeper than I expected with frost and freeze warnings in Utah and some heavy snows in the mountains of Montana and though neither unheard of this time of year its still rare.

tpweather wrote: ↑Mon Jun 13, 2022 7:51 am Good Morning and here we go with the heat and humidity. I have been on the low end with temps over the next several days. Will that be a bust and I have been watching this ridge expand more to the northeast instead of north so that may be a bust for me but first need to see how later today plays out. No doubt the mcs looks to be rather strong later today but will the expanding ridge push the strongest part of the mcs further north and east. I see the NWS has a excessive heat watch out for Tuesday afternoon and evening as they expect heat index to be near 109 in some places. Not sure we get that high but anything over 100 will feel quite nasty.

Great Post - it's like with the more northward push of the ridge we get more into the higher dewpoints and temps than expected earlier while the MCS train tracks shift more into northern Ohio. Do need to watch the separate system this evening because it will have lots of energy to work with.

Good morning guys! Great posts for me to catch up on this morning. I think we are just going to have to nowcast the severe part late this afternoon and evening. As mentioned models have been very inconsistent with the details. The possible overnight Derecho / MCS that is grabbing the headlines may miss folks S of I-70 to the north. But... will that have a tail on its southern end that gets us? Do we see the separate MCS from IN coming in from the NW as has already been discussed? We'll have to see when and if the cap breaks. The atmosphere is a power keg waiting to explode with development should the cap over us weaken and it should later.

After we get that mess sorted out... Excessive heat watches are up now for tomorrow. We will probably see warnings Tues - Thurs for the area. I am with Tim on the MAX temp at CVG being 92, but if that ridge is centered closer to us, then the mid 90s would be certainly possible. I think it's all dependent on where the ridge is and how high or atmospheric heights are. Usually around 590 means 90. 594, 595 or higher is usually the mid 90s. Models have been consistently showing the mid 90s but was you know, some of us have gone lower and you know the reasons why. We'll see! Regardless the HI's because of the tropical air mass in place are going to be 100-110 anyway so wither the apparent temp is 91 or 95, it's still hot and nasty!

Overnight AFD from the boys just to kind of re-hash things:


For today, the forecast is characterized by anomalously low
predictability. MCSs may traverse the Ohio Valley as a warm front
lifts into northern Ohio/southern Michigan and upper level ridging
builds. However, despite this synotpic setup being generally
favorable for MCS development, lack of consistent or clustered
mesoscale guidance highlights the challenges in forecasting the
potential MCS occurrence and track.

The one area of fairly high predictability is the overall storm
environment this afternoon. With the warm front north of the area,
hot and humid conditions quickly develop after sunrise leading to a
highly unstable atmosphere by noon (MLCAPE over 3000 J/kg). High
amounts of DCAPE are also forecast which justifies strong downburst
potential. Favorable thermodynamics overlap with 30 knot bulk
northwesterly shear this afternoon/evening indicating potential
storm organization. However, there has been no clear mesoscale
guidance supporting high probabilities of storms occurring or
ensemble clusters showing clear MCS paths.

As of the early morning forecast, two periods are highlighted for
the highest MCS potential. The first period is toward the later part
of the afternoon and early evening across the entire area but
especially eastern Indiana, and western/southwestern Ohio. Some
guidance depicts MCS formation in Indiana quickly overspreading into
Ohio and parts of northern Kentucky during the late afternoon. If
this occurs, strong damaging winds would be the main threat along
with some hail and tornado potential. This MCS would be of
particular concern since the atmosphere would not have had time to
stabilize yet. Locally heavy rainfall would also be a threat.

The second timeframe for elevated MCS potential is the
evening/overnight along and north of I-70. Storms may form
along the warm front in southern Michigan late this afternoon
before growing upscale and diving southeast into northern Ohio
toward the higher instability airmass overnight. Strong winds
would also be the main threat with this MCS along with some
hail. Hopefully any nocturnal MCS wind threat would be moderated
by a near surface stable layer. Can`t leave out the possibility
for locally heavy rain.

Please note this forecast will likely change and evolve today since
the outlook is characterized by low predictability. Check back
for updates through the day. If an MCS does form this afternoon,
there is some high end potential for wind damage given the
forecast environment.

So we are already building the foundation for potential action later this afternoon....DCAPE 1100-1200, SBCAPE 2000-2500 J/kg.