Sunday, April 14, 2019  2:45 P.M.

Cooler, drier air takes over

Thunderstorm chances have dropped to near nil as the atmosphere has rapidly drier this afternoon.  Still a chance for some showers over the next few hours as cooler air rushes in. Showers, if any, will be scattered with only about 30-40% areal coverage.

Winds, which did gust once to 40 mph at SDF have remained mostly in the mid to upper 30’s and will slowly diminish for the rest of the afternoon. Temperatures will also begin a rapid drop.

Stuff

Forrest Mars, the inventor of M & M’s, was allergic to peanuts.  Thus, he never got to taste his invention.

Sunday, April 14, 2019  12:30 P.M.

Thunderstorms possible

Sudden heating and increasing dew points for the past few hours have pushed us into an interesting weather pattern for the next 2-3 hours.  A rather diffuse low pressure system has been over us this morning (it brought us the overnight rain).  The low is now moving northeast into northern IN/MI.  That’s why we’ve seen the rapid increase in winds.  But, low level moisture is now dropping!  Also, in the wake of the low, a cold front is now marching from west to east across southern IN and KY.  The front should pass the I-65 corridor between 2 -3 P.M.

Ahead of the front scattered thunderstorms are popping up. Due to the decreasing moisture, no solid line of storms is expected.  But, some isolated storm or two could generate some gusty winds, perhaps (but not likely) even up to 50 mph.  Any thunderstorm threat locally will be over by 3 P.M.  Stronger storms, even a severe storm or two, could pop up over eastern KY later this afternoon.

About those winds…

1).  We are under a Wind Advisory this afternoon.

2).  National Weather Service Definition of a Wind Advisory is sustained winds of 31-39 mph for at least an hour and/or wind gusts of 46 mph to 57 mph.

3).  The current NWS forecast predicts wind gusts up to 40 mph.

4).  The current Hazardous Weather Advisory and Weather Advisory say gusts to 45 mph.

5).  Go figure!  Why issue an Advisory for something they aren’t forecasting?

6).  And, the prediction isn’t even going to happen.  The strongest wind fields are over eastern KY (east of I-75).  Locally, our wind gusts should top out in the mid 30’s.

Stuff

Q is the only letter of the alphabet that does not appear in any state name.

1:45 P.M. Thursday, March 14, 2019

1).  Signs  are showing the upper atmosphere and the lower atmosphere are beginning to “uncouple.”  Basically, that means that the “sweet spot” for severe weather production is fading away.

2).  The general weakening will allow the system to slow its eastward progression.

3).  Best time for Louisville now looks to be 4:30 until 6 P.M.

4).  Strong gusty winds (non thunderstorm) will continue.  Thunderstorm winds could be strong (50 mph or so), but tornado threat is lowering.

11 p.m. Monday, Feb. 18, 2019

Evening update

Evening model runs are, in general, running slower with precipitation onset tomorrow evening.  As a result, that gives more time for the atmosphere to warm.  Thus, the chance for snow has  changed to a very small window.

The result, and updated forecast, is now for rain to begin around 9-10 p.m. tomorrow night and produce 1″-2″ of rain by Wed. afternoon.  Rain may begin as a brief period of snow.  Little, if any, accumulation  is expected.

11:30 A.M. Fri, Feb. 15, 2019

Snow belt stays west and south of Louisville

No model run this morning shows any snowfall for southern Indiana or the Louisville area tonight.  1″-2″ snows are still possible along the KY/TN border area.  But the Louisville area will remain cold and dry.  NWS still persists with it’s 90% chance for snow tonight, but it’s just not going to happen.  Proper snow chance should be in the 10% to 25% range.

Next precipitation for Louisville area should come Sunday with some light rain likely.

Sorry, snow lovers, that’s just the way it is this time.

11 P.M. update 2/14/2019

Latest model runs are leaning toward no snow for the Louisville area Friday night/early Saturday.  Any accumulations will be south of Louisville.

Wed., Feb 6, 2019  4:15 P.M.

South Pole Winter video

Some fantastic video of the Antarctic Winter shot from the South Pole appeared today on http://www.spaceweather.com

Don’t just watch the video, also read how hard it is to operate cameras at the South Pole

Wednesday, Feb 6, 2019  11:30 A.M.

Lessening threat for flooding

Morning runs from the GFS and NAM both are lowering the rain estimates for the next 36 hours.  Since yesterday, radar rainfall estimates are under 1/2″ for southern Jefferson County rising to about .75″ along and north of the Ohio River.  Heaviest rain so far has been over southcentral IN.

Heaviest rain will shift into southern KY this afternoon as rain diminishes (for awhile) for northern KY and southern IN.  Periods of rain return tonight and tomorrow.  Now appears like the total will run between 1.5″ and 2″ for most of Louisville area with higher totals over southern KY.

Sat. Feb. 2, 2019

Early spring has arrived

We’ve now completed the cycle created by the Sudden Stratosphere Warming we began talking about about a month ago.  The breakoff vorticies from the polar jet stream have retreated northward to allow warmer air to take over.  The last segment of the polar vortex to hit the U.S. was extremely cold for the Great Lakes and northeast but moderated quickly as it pushed southward.  We didn’t even drop to zero ( 3 was the lowest), so it certainly wasn’t even close to “record breaking” as it was to our north and east.

With the polar jet now back home, the next few (maybe, many) systems to produce our weather will arrive via the Pacific Ocean, so they’ll be warmer.  And, with a little help from the Gulf of Mexico, probably wetter as well. The first will arrive Monday night.  Then, a large slow-moving system could provide periods of rain from Wednesday through Friday.

The GFS isn’t even hinting at decent snow chances for the next couple of weeks.  We’re going back to the West Coast Cold – Eastern U.S. Warm pattern that was prominent from late December to early January.  Get out your raincoat and put away the snow shovel for awhile.

The Groundhog

Punxsutawney Phil was rudely awakened from his hibernation around daybreak today.  His handler then read a statement “supposedly” from Phil.  The guy in the funny top hat announced that we’ll have an early spring.

The GFS and the seasonal model both say the same thing – early spring.  I consider that a far superior source for weather data.

Saturday, Jan. 26, 2019

Flurries tonight, Monday night is still a possibility

We’ve had some very light flurries early this morning, after sunrise, and again this afternoon.  Still, nothing to show for the effort.  But, this evening’s clipper may give us at least a dusting.

The weak clipper has be producing very light snow across southwestern Indiana this afternoon and is moving eastward.  It’s also weakening.  Very little snow (if any) will drop south of I-64 tonight, so this system will be mostly north of Louisville.  We’ll probably see some flurries twice this evening – centered around 6 and 11 P.M.  No more than a dusting is expected anywhere near Louisville.  Low tonight in the upper 20’s and not much increase tomorrow with highs about the mid 30’s.

Monday into Tuesday

For the past several  posts, I’ve been pointing toward a strong Alberta Clipper expected to move into the western Great Lakes early next week.  Models are now projecting the primary snow chance for us Monday evening.  South of Clipper Monday, we’ll see see strong southwesterly winds and a quick warming into the 40’s.  The cold front trailing the clipper will push across central IN/KY Monday evening.  That will bring us the coldest air mass of the season Tuesday through Thursday.  Temperatures should drop to the lower single digits a couple of days.

What about snow?

Yesterday I mentioned the (to me) unusually high amount of precipitation the GFS was projecting with that front.  The weather south of clippers is usually quite dry.  Today, the GFS forecast reduces the rain/snow totals considerably.  The NAM is also low.  That seems much more reasonable to me.  But, it also reduces the snow potential to less than an inch.  It’s early, things could change.