Sunday, April 12, 2020   4:30 P.M.

For the past two days the Storm Prediction Center has been predicting a major severe weather outbreak over the deep south into central Tennessee.  They have been including KY and southern IN in the “slight risk” area, but their discussion has included several “ifs” for us.  In essence, plenty of uncertainty for KY/IN.

As the situation has been evolving today, there’s been a good news/bad news scenario developing.  Bad news for the deep south means good news for us.  Mississippi has been hit this afternoon and things look very bad for Alabama, central TN and Georgia tonight.  That major outbreak will block some needed severe storm ingredients from traveling this far north. So, even though we’ll see two periods of showers/thunderstorms tonight, the threat for “severe” thunderstorms will be very low – less than 5%.

Showers/thunderstorms in the local area now will move northeast of Louisville by 8-9 P.M.  Then, we’ll have a 5-6 hour period of dry weather along with rising temperatures!  Another period of showers/t-storms will arrive with gusty winds a couple of hours after Midnight.  This rain system should end during the morning rush hour.

Tomorrow will be cloudy, very windy and cooler.  Temperatures should drop into the low to mid 50’s tomorrow morning and stay steady during the afternoon.  The winds will be tomorrow’s weather feature with frequent gusts over 30 mph and a few gusts over 40 mph possible.

Monday, March 30, 2020  11 P.M.

I’ve been puzzled since yesterday about the NWS forecast for a 50% chance for rain tomorrow.  All the models have been keeping the rain south of Louisville.  Tonight’s models keep the rain even farther south.  50% seems far too high for Tuesday.  So, a mostly cloudy sky with pleasantly cool temperatures in the 55-58 range appears likely.

Thursday,March 19, 2020

Flash flooding likely: severe storms iffy

A fairly strong upper air disturbance will come across the lower Ohio Valley tonight.  Lucky for us, it’s focused mostly on Indiana.  With this upper system, we’ll see two clusters of thunderstorms overnight.  With the rains of the past two days, periods of heavy rain, especially over southern IN, will pretty much guarantee widespread pockets of flash flooding over northern KY and southern IN.  If you live in a flash flood-prone area, you know the drill.

The first cluster of thunderstorms will be over the area this evening.  The southern side is weak and will provide plenty of rain to west and central KY and initiate some of the expected flash flooding.  But no severe thunderstorms.

The first cluster of storms will be more noteworthy over the southern half of Indiana.  Severe storms are moving over southern Illinois and will race eastnortheastward.  Heavy downpours are likely and a few severe storms will be possible between, roughly, 8 P.M. and Midnight.  Primary threat will be strong winds and possibly some hail.

The second cluster of storms will move through the area between about 2 A.M. and 8 A.M.  This one is much stronger and is likely to produce an outbreak of severe storms from Arkansas, southeast Missouri and southern IL this evening.  By the time this cluster arrives in the Louisville region, it is likely to be weakening.  Plus, atmospheric instability will be diminishing. Also, the strongest dynamics will remain north of our area.

The result will be a very noisy night north of the Ohio River.  Flash flooding will probably become  a serious problem.  Storms will be strong, but probably not severe.  Along and south of the Ohio River, the primary line of thunderstorms most likely won’t arrive in Louisville until 5 A.M. or later.  They will not be very strong, but deposit enough rain to make a very messy rush hour before the exit the area by 8 A.M.

Strongest storms will stay south and west of Louisville

Thursday, March 12, 2020  4:45 P.M.

Latest radar trends and short term forecast models are strongly indicating that we’ll get plenty of rain this evening, but severe weather will not reach the Louisville area.  Severe storms are forming along the approaching cold front over western KY and dropping rapidly southeast.  That area of severe storms is heading toward central Tennessee.

Meanwhile, area of showers and non-severe thunderstorms has been expanding over  SW IN and is moving our way.  Cold front may produce some gusty winds as it passes through the Louisville area between 6:30 and 8:30 this evening.  Our biggest problem will be with heavy rain and possible areas of flash flooding.

Thursday, March 12, 2020  4 P.M.

Cluster of rain/thunderstorms in the area now is not showing any signs of severe weather,  Instability is very low, but the dynamics are quite strong.  Nevertheless, severe weather is not expected with this area.  However, stronger storms appear likely later this evening.

Current showers/t-storms are forming along a warm front slowly pushing north.  Once we get into the warmer/moister air south of the front, we’ll have the potential for slightly higher instability for a few hours.

During that time, a cold front will be moving over southern IN/western KY.  That system should pass through our area between 6 and 8 P.M.  The front is already creating severe weather to our west.  Instability should still be weak, but the wind fields will be strong enough to create a strong wind threat – possibly severe (58 mph or more) in a few areas.  Atmospheric structure favorable for tornadoes should remain south and west of Louisville.

After 8 P.M., threat for severe weather will move south and east of Louisville area.

Fri., Feb. 7,2020

Weak Clipper brings a little more snow

A weak Alberta Clipper dropping into the Ohio Valley tonight and tomorrow morning will leave a minor calling card in its wake.  Available moisture is lacking and the clipper does not appear strong enough to force much lifting this far south.  The clipper’s path is expected to pass over southern IL/IN.  That sets up central IN for a possible 1-3″ accumulation tonight and early tomorrow.

Meanwhile, south of a clipper’s path, not much happens.  In reaction to the clipper moving north of us, we’ll see southerly winds tonight.  That’ll hold temperatures in the low to mid 30’s.  Precipitation south of a clipper’s path historically is little or none.  So, even though some light snow is possible late tonight and tomorrow morning, accumulation will be in the “little or none” category.  Probability for measurable snowfall is about 50%.

Tomorrow morning marks the last snow chance for about a week, at least.