Thursday Night Update....

Friday looks to be the hottest day of the year so far as gusty southwest winds, lots of sunshine, and the thermal ridge right over the area means the temperatures will reach for that 90 degree mark by late afternoon. BTW, did you know the last time we reached 90 degrees or more in Louisville... 234 Days ago !!!!! nearly 8 months !!!. On Oct. 8th, 2007 the high reached 93. It has not been in the 90s since.

Big storms with hail, damaging winds, and tornadoes have been occurring across the plains states tonight. The system responsible for the severe blow up is shifting east, northeast but is also weakening. Check out SPC's day 2 for tomorrow / tomorrow evening... ???

Looks way overblown to me at this point and would not be a bit surprised to see them cut back their areas of moderate - and maybe even cut it out all together.

I think Friday will be a dry day with lots of sunshine. Capping seems to build into the area as the afternoon wears on. GFS progged sounding showing a well mixed low level (850mb and below). and fairly warm mid-level temps... (~ H7). This trend should hold through Friday evening with the best area of storms holding north across central Indiana through midnight. Later Friday night into Saturday morning, the thunderstorm area will continue to sag south into the viewing area but should be in a weakened state and becoming more scattered basically for several reasons....

1) convergence along frontal boundary is weakening quite a bit as night wears on...
2) best dynamics / large scale lifting stay to our north...
3) weakening instability as Blayer cools .

Bottom line... not expecting a big time severe weather outbreak for the area...
Best rains chances should then shift south through the day Saturday as the weakening frontal zone continues to push slowly south ionto the Tennessee valley...

Enjoy the Friday heat all...

Later:
Jay

Severe Weather ???... NOT Around Here (Wednesday am update)

Overall the active weather pattern will continue... but we have managed to escape the big severe weather outbreaks so far this Spring and I think that trend will continue for the next week to 10 days !!! Good for Us !
It will stay unsettled, however, as another H5 short heads in our direction for late tonight through tomorrow and give us more rain and perhaps a few rumbles of thunder.
Here's the setup... H5 wave passing through the lakes will push a weak boundary through the region tonight...












Frontal boundary will then stall to our south and provide a classic overrunning situation for the NewsChannel 32 viewing area. Southwest H5 short will move northeast and begin to minor out but still have plenty of energy to induce low level cyclogenisis on the boundary.












Low level WAA / isentropic lift will dramatically increase late tonight and pretty much all day tomorrow as system approaches from the southwest. Sfc feature as well as H9 & H85 lows are expected to track south of Louisville - -- perfect set up for persistent rainfall and some embedded thunder (and some of the rainfall will be locally heavy. It looks to me as if a widespread 1 to 2 inches of rain is likely with some locations, a bit more.















Stay dry...
Later:
Jay

Sunday Morning Update (Mom's Day)

Hello... not sure a severe weather outbreak can get much closer.... missing us to our west and south yesterday where numerous tornadoes and fatalities were reported and today - just (and I mean just) to our east.

The cold front came through earlier this morning and interacted with minimal instability to produce scattered thunderstorms... Once the storms popped they tapped the strong dynamics aloft and some of them quickly became severe across the viewing area producing isolated pockets of wind damage - mainly north and then just east of Louisville. By mid / late morning, the broken line had intensified producing large hail, damaging winds, and numerous tornado warnings for areas just east of the NewsChannel 32 viewing area - If that's not close and lucky - at least for the viewing area... I don't know what is !!


Rest of the day will feature gusty winds, scattered showers, and chilly temperatures as the upper low continues to spin across the Ohio Valley - - in a nut shell... it's going to be nasty out there for Mother's day - sorry moms !!!

Looking ahead... conditions quiet down
Upper low will continue spinning east away from us ans as H5 cyclonic jet axis shifts east of us, any low clouds on Monday morning will break up as good low level mixing takes over. The afternoon hours on Monday should feature a generous amount of sunshine although it will stay quite breezy through midday as low level winds up to H85 are coupled and blowing between 15 to 20 kts. Decent mixing should translate winds of 10 to 20 mph at the surface before the gradients relax and winds die as we progress deeper into the afternoon.

Tuesday.... A great day - mostly sunny skies, ridging in place, and with H85 temps progged to be in the +12 range - mixing should allow for temperatures to easily warm into the upper 70s!!

Next system affects us on Wednesday but this system will be quite weak as one piece of H5 energy stays well north and another stays south/southwest and weakens as it pushes eastward. As a result... at this time I don't see much (if any) severe weather for the upcoming work week.

Long range... upper trough will be establishing itself across the eastern half of the lower 48 so don't expect any long term warmups at least for the next 1 to 2 weeks - if anything temperatures will likely average out to be below normal.

Happy Mother's Day all

later:
Jay

Monday Update

Well, the 134th running of the Kentucky Derby is in the books and all-in-all the weather for the 3 week festival turned out to be half way decent this year - actually prett nice... The only problems we had occurred on Balloon Race morning - although it turned beautiful for the balloon race later that day, and of course for Oaks Day - talk about a washout, and that makes 2 years in a row for wet weather on the Oaks.

Time to look ahead now, weather looks very quiet the next 3 days - through Wednesday. On Thursday and then possibly into the weekend, the next chance for rain will invade the Ohio Valley.
Pattern is very "blocky" across North America east across the Atlantic into Europe. Check out the hemispheric H5 pattern... 2 Omega blocks side by side and we are positioned on in the troughiness on the front side of the Omega block across N. America.












So what does this mean ?? Overall, no major, persistent warm ups on the way until this pattern breaks down - and that is not really progged to happen until next week at the earliest. Will we see 70s and perhaps an 80 degree day this week - absolutely !! But we will not see persistent 80s.

This blocky pattern will force systems that are coming into the west coast to head farther south (under the block). As a result they will not pull the real warm air way up into our area.

One such system will affect us this Thursday. An H5 low now in the southwest U.S. will get kicked east towards Mid-America. As it continues east it will run into an increasingly confluent flow (because of the block) and weaken / start to minor. This system will move across our region on Thursday with good chances for showers and Thunderstorms.











It looks like 2 other fast moving upper systems will shift rapidly east under the above mentioned block as we head into the weekend. One for Friday night into Saturday Morning, and the other on Sunday. Both these systems will bring rain chances to the Ohio Valley as an overrunning pattern will likely occur as upper vorts interact with a frontal boundary that is progged to be to our south.












With the boundary to our south through the weekend, temperatures will average out to be quite cool.

We'll keep you posted... Have a great Monday
Later:
Jay

Thursday Update....

Weather forecast seems to be holding up quite nicely and on target with the latest data coming in...
NAM still giving us an isolated chance for Oaks afternoon - but the latest info is indeed less bullish with the coverage near Louisville and more in line with that of the GFS qpf field.
Still - if you're heading to the track, take that poncho just in case..

Main batch of showers and storms will arrive late Friday night into Early Saturday morning - This batch of storms will be severe west of us, but by the time it gets here, it will likely be in a weakened state as it outruns its best support. Even the 0-6k shear values really taper over us from what they will be west of us.

Showers and storms will be diminishing Saturday morning with partial clearing taking place by late morning/midday. Temperatures warm back into the 70s, and then as another strong H5 vort lobe and the actual sfc cold front with this system move across the viewing area, another round of showers and storms will likely develop Saturday early to mid afternoon. I actually think this will be our best opportunity of seeing any strong / severe storms. Don't see a lot of twisting - helicity vallues are quite small but the 0-6k shear values are 60kts plus and the front will be interacting with a moderately unstable atmosphere...

This would suggest that any storms that do form will be capable of producing damaging wind gusts and hail... SPC hs slight risk for Saturday south of us, but I think there's a good chance that will be expanded to include us as well.

We'll keep you updated .

Later:
Jay