Chad’s WLFI Weather Blog

Climatology of the Last 80° Temperature In the Viewing Area

September 30th, 2014 at 6:05 pm by under Chad's WLFI Weather Blog

Still working on this.

210

Image

221


High Evaporation Rates Over Past Two Weeks Big Benefit to Farmers

September 30th, 2014 at 1:40 pm by under Chad's WLFI Weather Blog

At the Purdue ACRES site (this is NOT the Ag Farm, it is actually near the White County line off I-65 on 900 W), evaporation & rainfall are measured with automated equipment.

Nearly 10″ of rain fell at this site August 1-September 15.  During that time frame, 4.29″ of water evaporated.  Since September 15, we have evaporated around 1.60″ of water.

In fact, the evaporation rate on Sunday was 0.15″ in a 24-hour period at this site.  This was the highest evaporation rate since September 6.  Prior to September 6, only three days have had evaporation rates of 0.15″ or greater in the 24-hour period.  Those dates include August 5, July 10 & July 5.

__________________________________________________________________________________________________________________________________________________________

At the Ag Farm site near Romney, it has been drier than the ACRES site.  August 1-September 15, 8.26″ was measured.  During that time, 4.09″ of water evaporated.  Since September 15, that site has seen upwards of 1.50″ evaporate.

Interestingly, there has been greater variation in evaporation rates at the Romney site.  Evaporation has equaled or exceeded 0.15″ seven times since July 1.  It has only been three in the wetter area in northern Tippecanoe.  However, slightly more water evaporated, overall, in northern Tippecanoe.

Regardless, the higher evaporation, on average, lack of rainfall & sun have all contributed to grain drying & drying of soils over the past 2-3 weeks, which has greatly benefited farmers in the viewing area.

201


Remembering the ’99 Supercells……..Outlook Based On Latest Data

September 29th, 2014 at 8:49 pm by under Chad's WLFI Weather Blog

If you experienced these storms, I would love to hear your memories of them!  Thank you for sharing, in advance!  -Chad

September 28, 1999 – The Autumn HP Supercells


Three high-precipitation supercell t’storms popped on the outflow boundary from morning/afternoon rain/storms to the north & west amidst a hot, humid airmass on September 28, 1999.  Ahead of a strong fall cold front that was to usher in the first light frost of the season & under strong jet stream winds amidst substantial wind shear, the cells very rapidly pulsed up & became severe.  The first report of severe weather was a 58 mph wind gust at Pine Village.  This was the beginning of a long track of destruction across the heart of the WLFI viewing area from as the three supercells evolved into a cluster, then bowing line segment.  Flash flooding was an issue with these high-precipitation supercells & 3 corridors of substantial flash flooding developed as extreme rainfall rates occurred.  You can certainly understand why this event is one of the top autumn severe events.  Imagine +100 mph downbursts, 2-3″ per-hour rainfall rates & golfball sized hail.  In fact, up to 6″ of hail accumulated on the ground 1 mile north of Buck Creek & old State Road 25 was close northeast of Lafayette by up to 4″ of hail on the roadway.

Interestingly, after the storms, very dense fog formed over these areas that had so much hail, making travel difficult.

The rain was very welcome, however, as the area was in the midst of a significant drought.

Supercell #1:  Pine Village to South of Yeoman

Reports of extremely high winds began in northeastern Warren County, then continued east-northeastward, blasting Montmorenci, West Lafayette & Klondyke.  The highest measured non-tornadic wind gust on record in our viewing area occurred from this storm with a 103 mph gust near Montmorenci.  Hundreds of acres of corn & soybeans that were about to be harvested were totally flattened by the apparent macroburst (damage diameter greater than 2.5 miles).  A 5th-wheel camper was overturned, injuring the occupant & 2 dozen homes received damage.

Numerous trees were blown down in Pine Village & several roads were reportedly blocked by fallen trees in Lafayette. As I said formerly, an amazing hail depth of up to 6″ was reported 1 mile north of Buck Creek.

The storm continued east-northeastward & dropped an F1, 105 mph tornado on the southwest corner of the supercell, which tracked 4 miles to east-southeast to near Buck Creek.  Up to a half-mile wide, it produced over $300,000 in damage.  3 farm tool sheds were totally destroyed with the structural debri found in the tops of trees as far as 1-2 miles away.  With the tornado touchdown, golfball-sized hail began to fall from the storm.  A second downburst (in this case a microburst) belched from the storm with a measured wind gust of 64 mph at Buck Creek.  There is evidence of wind gusts to 80 mph east of Buck Creek.  This combined with golfball hail caused siding & roof damage to several homes & destroyed fields of unharvested crops all the way to western Carroll County.  Gaping holes were ripped in roofs by the wind-driven large hail.  Route 225 was impassable due to fallen trees.

Supercell #2:  South of Attica to Flora

Golfball-sized hail began to fall with this supercell southwest of Lafayette.  In Lafayette proper, $100,000 in damage was done (largely to cars).  Large hail continued with the storm with northeastward progression.  Golfball hail was reported at Radnor & Flora.  The first downburst (microburst) with this storm occurred near Radnor with a 64 mph wind gust measured & an 80 mph gust causing substantial tree damage.  A barn was destroyed by this microburst.

In White County, southwest of Brookston, the large hail core accumulated a snow-like covering several inches deep.  Radnor, in Carroll County also reported golfball-sized hail with substantial hail accumulation with a wind gust to 64 mph, as a third microburst was belched from the storm.  A barn was destroyed east of Radnor with estimated microburst gusts around 80 mph.  Golfball-sized hail was reported at Flora.

Supercell #3:  South of Otterbein to Brookston to Fulton (Storm Continued Northeastward with Sporadic, But Impressive Damage to Near Fort Wayne)

The third severe supercell popped just south of Otterbein, tracked into White County & began to produce a prolific golfball hailstorm.  Hail accumulated several inches near Brookston.  Entire fields of crops were destroyed & trees were totally stripped of leaves.  The storm continued northeastward with several inches of golfball hail in northwest Carroll County.  The first downburst (in this case microburst) was belched out northwest of Logansport with a 75 mph wind gust that caused tree & power line damage with crops fields damaged.  The storm then belched out the second extreme macroburst of the evening with 100 mph wind gust doing heavy damage southwest of Fulton to  Nyond Lake & South Mud Lake.  This macroburst alone produced over $125,000 in structural damage.  This storms second gust, a microburst, produced tens of thousands of dollars in structural damage north of Macy in Miami County. This same storm produced winds up to 80 mph in Whitley, DeKalby & Allen counties.  Significant damage to trees & powerlines occurred in Columbia City with many homes receiving minor structural damage.  Much of the city had no power for at least 24 hours.

The damage costs to these supercells were phenomenal.  In Tippecanoe County alone, just the hail caused over $100,000 in damage to structures.  Damage to automobiles was upwards of an additional $100,000 (Tippecanoe County, alone).  +$100,000 was done to structures via damaging winds.  $300,000 in damage was incurred by the tornado.  Crop damage in Warren, Tippecanoe, White, Carroll, Cass, Fulton & Miami counties mounted into the tens of millions of dollars as thousands of acres of crops were flattened or completely destroyed.

_________________________________________________________________________________________________________________________________________________________

What a stretch we have had recently!

202

Front will slide through late tonight-Tuesday morning, turning skies cloudy to mostly cloudy with an isolated shower possible.

Data shows clearing trend in the afternoon with 66-76 for highs.

Front will move right back northward tomorrow night in response to approaching storm system.

203205201207208

Two waves of showers & t’storms will pass Thursday afternoon-evening & another night-Friday morning.  The heaviest one looks to be Thursday night-Friday morning.

Right now, the severe weather threat zone is South Dakota to Arkansas to as far northeast as southwestern Illinois Thursday-Friday.

209


7:37 P.M. Update

September 29th, 2014 at 7:37 pm by under Chad's WLFI Weather Blog

Today was another warm one with 79-85 after patchy dense fog & upper 40s to mid 50s this morning.

DMA Map II

Cold front will approach tonight & pass tomorrow morning.  We will drop to 50-56 tonight, then rise as front approaches to 55-60.

There will be a considerable amount of cloudiness with it as it passes & followed the passage.  I cannot rule out an isolated shower or two/sprinkle (mainly in our northern/northeastern counties) as it passes.  Models tend to clear the clouds in the afternoon or at least just have scattered fair weather cumulus.  Went “mostly cloudy in the morning, then decreasing clouds in the afternoon” for forecast wording as a result.

It will keep highs at upper 60s to upper 70s tomorrow with 47-56 tomorrow night.

However, front will move right back north tomorrow night & Wednesday & Thursday will warm up again.

Looks like one wave of scattered showers & t’storms Thursday late, then break, then main wave of rain/t’storms Friday.  Right now, looks like best estimate of timing is Friday morning.

Locally-heavy rainfall of 1-2″ in places is still possible.  Despite good dynamics, instability will be an issue.  With lack of it, severe weather does not look like an issue right now, but we do need to watch it for any changes.  It is possible that greater instability may develop & lack of severe threat need be re-evaluated.  Severe weather is still likely in the Plains to western & southern Illinois.

Cooler weather will come in Friday-Sunday with highs only in the 50s Saturday.  A couple/three nights over the weekend, even early next week will see widespread 30s with some frost.


Latest Outlook

September 28th, 2014 at 10:38 pm by under Chad's WLFI Weather Blog

Highs Sunday ranged from 79-85 with lots of sun with only some wispy cirrus & a few fair weather cumulus in the area.  After 50s & some patchy fog tonight, we will be back to 79-84 tomorrow with plenty of sunshine.

DMA Map II

I think we will fail to reach 80 in the area Tuesday as a weak, dry front comes through in the morning.  We will still see 70s, though.  There may be some clouds with the frontal passage in the morning, followed by  lots of sun & a north-northeast wind at 10-15 mph.

This front is in response to strong upper trough & surface cold front swinging through Manitoba, Minnesota to Ontario & Quebec just skimming area.

The front will tend to work right back north by Wednesday with highs back at 79-84 after 47-56 in the morning.  The wind should go back south as front lifts northward through area after 3 a.m. early Wednesday morning.

Scattered showers & t’storms are likely Thursday late with peak in coverage Thursday night, followed by another wave of widespread rainfall & t’storms Friday.  Dynamics/shear are great, but instability is lacking due to widespread rainfall, which appears to diminish any severe potential at the moment.  We will watch.  Severe weather is likely Kansas to Missouri to western & southern Illinois to Arkansas.

Here, locally heavy rainfall of 1-2″ is possible in parts of the area.

Cooler air will follow.  Highs by Saturday will only run in the 50s with lows in the 30s.  With 50s to around 60 Sunday, lows will be in the 30s.

A rapid warm-up back to 70s is possible after this with overall pretty dry conditions.


Latest Outlook Out Later This Evening

September 28th, 2014 at 8:34 pm by under Chad's WLFI Weather Blog

The latest outlook will be out later this evening.


11:45 P.M. Update

September 27th, 2014 at 11:03 pm by under Chad's WLFI Weather Blog

Highs today varied from 79-84.

Tonight, patchy high/mid clouds will exit & patchy, locally-dense fog will develop with lows of 51-56.

Sunday & Monday look great with brilliant sun & highs from around 80 to as high as 84, with lows in the 50s with some patchy fog.

Again, Tuesday looks a hair cooler at 77-81 with 79-84 Wednesday & 78-83 Thursday.

234240

It looks like scattered showers & t’storms will come in Thursday & increase Thursday night, followed by a main round Friday.  It is still a bit questionable when exactly the heaviest showers/storms pass (with cold front) Friday & if any rainfall will linger into Saturday morning.

Regardless, storm system looks pretty strong with strong wind fields at all levels & good forcing.  For us, question is instability.  If it can get unstable enough, then severe threat would need to be put in place.  The latest data still suggests an issue of getting unstable enough for severe threat, but it looks plenty unstable enough from Kansas to Iowa to western Illinois to Missouri & Arkansas for severe event late week.

It also still appears that locally-heavy rainfall may occur with widespread 1-2″ amounts.

Much cooler weather still looks to follow with a couple nights in the 30s before the warmth rapidly returns.

We will continue to monitor & tweak forecast as needed as additional data arrives.


Latest Outlook Now-October 10

September 27th, 2014 at 4:12 pm by under Chad's WLFI Weather Blog

Patches of high & mid clouds splotch the sky with warm, nice sunshine.  The deeper 850 mb moisture for fair weather cumulus remains Indy metro & southward & that is where they have formed today, rather than farther north into our area.  This is close to where the 60-degree dew point line is generally located.

Tonight, with patchy high/mid clouds pulling away, patchy dense fog is possible.  Lows will run 51-56.

201202203

Sunday & Monday look great with lots of sun & highs back to 81-84 with lows in the 50s.  It will cool just a hair Tuesday with highs at 77-81.

205206

Wednesday & Thursday will return back to 81-84 with lows by Wednesday & Thursday nights in the 60s.

207

Data continues to show a gusty, windy system with several waves of showers & t’storms Thursday to Friday & perhaps Saturday.

There is a question as to whether the front will pass Friday at some point or as late as Saturday.  This will become much more apparent in the coming days.  With the models wobbling back & forth, I would prefer to let the dust settle before settling on an exact day of frontal passage.

Regardless, it appears scattered showers & t’storms are possible by late Thursday as cold front & first surface low approaches.  These may increase in coverage Thursday night, before a break ensues.  Strong south-southwest winds of 20-30 mph will likely be steady through the afternoon-night.

Although it appears that Hurricane Rachel remnants will not make a right turn toward the U.S. per National Hurricane Center forecasts & long-range data, there is a lot of deep tropical moisture that will likely be pushed northward.  So, I still think locally-heavy rainfall is good wording.

210

As for Friday or Saturday, several things can be discerned:

1)  It is likely that a strong upper jet streak (core of very strong winds way up in the troposphere) will swing in from the southwest & cause second surface low to deepen rapidly over northeastern Illinois.

2)  Dynamics are forecast to be strong & shear impressive with fall system that will deepen from 1002 mb to about 992 mb in 10 hours in its track from Missouri to Michigan.

3)  It is likely that severe weather event will unfold with this deepening from Oklahoma to southeastern Iowa, Missouri & western Illinois to Arkansas.

4)  Here, issue is instability.  Today, CAPE forecasts are not impressive here at 200-500 J/kg.  Forecasts have been more impressive in previous days.  This said, it is too unclear how surface instability will evolve to put much forecast on severe outlook for our area.  We will just have to monitor.  My confidence is much higher in severe threat west & southwest of our area, than here.

5)  Timing is an issue.  Prior, data suggested Wednesday-Thursday rainfall time frame, which slowed to Thursday-Saturday.  Recently, there has been that Thursday-Friday trend.  This also said, I can tell you that I can pinpoint the rainfall potential down to Thursday late-Thursday night & again Friday.  Whether the actual front & best lift come through Friday morning, Friday afternoon or Saturday morning is in question………………heck it may end up being Saturday afternoon.  It is too hard to say this far out.

To combat this issue, I took a medium road with frontal passage & best lift coming through in the Friday to Saturday morning time frame.  This will remain the wording until early week when I can get a better handle on it.  We may even see temperatures drop from the 60s Saturday morning to 50s in the afternoon.

6)  I still like the mention of locally-heavy rainfall (1-2″) even in the Friday-Saturday time frame, given the lift & tropical moisture.

212213214215

On thing is for sure, it will cool off rather quickly & dramatically from 80s for highs to 60s, then 50s behind this system.  A couple to perhaps three nights may see lows in the 30s in the viewing area.  Frost is possible.

210

The good news it that trends point to this rather ordinary early-October cool wave being brief.  60s & 70s may return again thereafter with drier weather.


Latest on Outlook Through Next Week & Beyond

September 26th, 2014 at 9:55 pm by under Chad's WLFI Weather Blog

More torrential rainfall & severe t’storms are hitting the Desert Southwest again.  More rain is also overspreading southwest Texas.

Check out the obs for the North Las Vegas, Nevada area:

1

Highs today ran 81-85 with mostly sunny skies.  Some fair weather cumulus mixed with cirrus will be with us Saturday with highs in the 80s after 51-57 in the morning.

Highs, with mostly sunny skies, will run in the 80s Sunday & Monday.

210229228232

We will likely remain near 80 to the lower 80s Tuesday-Thursday.  We might shave a couple of degrees off, but it will remain mostly sunny.  Lows will run from near 50 to the upper 50s, except around 60 to the mid 60s Wednesday & Thursday nights.

Data still suggests showers/storms late Thursday-Friday to perhaps Saturday with deepening surface low.  Dynamics are ample, but instability is questionable for severe weather.  It still needs to be monitored.

A few days with highs in the 50s & lows in the 30s with frost looks to be followed by a pretty rapid warm-up.


80s Now………..Some Frost Soon………Frost/Freeze Climatology

September 26th, 2014 at 4:45 pm by under Chad's WLFI Weather Blog

It is nice & warm today, but as we get ever closer to October, it is good to into frost/freeze climatology for the area.

208WEST LAF DATAWEST LAF DATA IIWEST LAF DATA IIIWEST LAF DATA IIII205205