Chad’s WLFI Weather Blog

Accumulating Snowfall Southwest of Our Area

December 17th, 2014 at 10:08 pm by under Chad's WLFI Weather Blog

Most models completely dry up absolutely all of the snow over Missouri to Illinois tomorrow as it moves eastward.  This will partially be the case as high pressure acts as a wall to this system & any movement northeastward.

However, I would not be surprised if at least some snow showers last long enough to get in here.  I still like 20% POPs for tomorrow for snow showers with any accumulation being less than 1″.  We will monitor this, as if the snowfall holds together even better, then POPs would need to be increased.

Right now, some very intense banding of snowfall is occurring in east-central Kansas & over south-central Missouri with locally 1-2″ per hour rates.

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Several Systems Of Note Through Christmas

December 17th, 2014 at 1:49 pm by under Chad's WLFI Weather Blog

TONIGHT-THURSDAY……………….

A general 1.5-4″ snowfall is likely across Kansas, Missouri & western Illinois tonight-Thursday.  However, I think two main band of intense band will dump 4-6″.  One is likely in Kansas, the other in central Missouri.  Band #1 in Kansas will largely be in frontagenetical forcing at first, then become a deformation zone of intense snowfall.  Band #2 will be a focus of intense frontagenetical banding in Missouri.  This is also where baroclinically-induced, nocturnal low-level jet will forcing moisture & bits of elevated instability (which will enhance the snowfall).

Now, this system will encounter wall of surface high pressue in our area Thursday afternoon & rapidly fall apart.  However, there are subtle model indicators that suggest some scattered snow showers may hang on just long enough to make it into our area later Thursday with perhaps a dusting in places.  Confidence is not high on that, but is such that 20% POP is warranted & inclusion of a “less than 1″” potential zone painted.

NWS has Winter Weather Advisories up in these areas & they may put out localized Winter Storm Warnings eventually in those zones of greatest forcing.

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SATURDAY…………..

Second system may spread a 1-2″ band near the Ohio River Saturday.  If we would happen to get anything from that, it would be very light.  We will continue to monitor.

I still  have 20% POP for Saturday for any snow shower, due to some degree of uncertainty.

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NEAR CHRISTMAS………….& BEYOND……………

Still looks like colder regime around Christmas.  We will have to keep an eye on third system that will bring accumulating snow to parts of the Rockies & Plains.  Potential is still there for snow around Christmas.

Christmas Day still looks windy & cold with highs in the 20s & lows in the 10-15 range.

There is some earmark of a brief, sharp warm-up of 40s to perhaps 50 for like one day, but I do not know whether that is before New Year’s.  Timing is blurry at best, but there is like one day of intense warm air advection with quick warm-up.  I hope to pin the timing down in upcoming posts.

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Latest Outlook to January 1

December 16th, 2014 at 11:05 pm by under Chad's WLFI Weather Blog

Cold air got in just before last of the drizzle ended, leading to period of grainy light snow.  Some of you may have gotten a powdered sugar dusting.

Lots of clouds will dominate the rest of the week & into the weekend with highs in the 30s.

There are three snow systems to watch to December 26.

System #1 will bring 2-4″ of snowfall to parts of eastern Kansas & Missouri & perhaps 1″ as far east as central Illinois Thursday.

Right now, it looks like this system will die out rapidly as it encounters strong high pressure over our area.

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System #2 will likely track farther south with band of snowfall perhaps along the Ohio River to the Northeast.  Here, it may bring a few snow showers Saturday.  If there is any accumulation it would be less than 1″.

System #3 looks to dive out of the front range & bring scattered rain/snow to our area initially around next Tuesday.

Widespread accumulating snowfall is possible Colorado to Missouri.  There is uncertainty regarding how much influence it will have here, but some data suggests some accumulating snowfall just before/around Christmas.

It still looks like a cold Christmas with highs only in the 20s & lows of 10-15.

There are signs of a brief, sharp warm-up near New Year’s to 40s, perhaps 50.  However, confidence is not high on that, still.

 

 

 


Drizzle Changing to Snow Grains Before Exiting

December 16th, 2014 at 10:10 pm by under Chad's WLFI Weather Blog

Drizzle is hanging on long enough to change to snow grains as of 10 p.m. as temperatures drop aloft & at the surface before the drizzle exits.  A light dusting is possible.  It is still all drizzle in the far northeast.  Watch for slick spots.

Lows tonight will drop into the upper 20s to around 30.

With cloudy to mostly cloudy skies tomorrow, a few flurries are possible.  Highs will run near 36.

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Falling Temperatures………..Latest Outlook to Christmas

December 16th, 2014 at 2:37 pm by under Chad's WLFI Weather Blog

Of the rainfall totals I have, totals vary from 0.13″ to 0.45″ across the viewing area as of 3 p.m.

Lowest total is 0.13″ at Kentland & highest, 0.45″ near Logansport (though the airport AWOS has only measured 0.25″).

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Spotty showers/drizzle are possible into the evening, though the widespread showers/drizzle will tend to gradually exit.  Temperatures are falling with windy conditions (gusts to 31 mph at times).

As of 3 p.m., it is 39 at the station after a high temperature earlier at 47 as the colder air actually wraps in from the southwest around the low.

Any rain will exit by later this evening & the winds will decrease after 9 p.m.

Models want to clear skies out tomorrow & Thursday, but I am highly doubtful.  I think mostly cloudy to cloudy skies will be with us (low stratus) tomorrow-Saturday.

Although I cannot rule out a few breaks perhaps here & there tomorrow-Friday, but I highly doubt we will see much sunshine until next week.  I hope this changes!

Highs will run in the mid 30s with lows in the mid to upper 20s the rest of the week.  Tomorrow, west-northwest wind will run 10-15 mph, but the winds Thursday-Friday look light at just 5-10 mph from the west & northwest, before turning north & northeasterly Friday night.

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In terms of snowfall potential by Saturday, data still suggests the main area of accumulation will be southwest of our area.

One system will tend to dump its load in Kansas & Missouri to western Illinois, then  slowly weaken as it bumps into wall of high pressure, while the second system will tend to curve around to the south & produce most of its snow from the Ohio Valley to the Northeast.  Up to 9″ may fall in New England with 4-6″ over parts of Pennsylvania & New York State possible.

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Now, there is a third system to monitor for passage here/nearby closer to Christmas.  A band of accumulating snowfall is likely with it, but like the Friday-Saturday systems, it is hard to tell who will get the White Christmas.

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Flash of Lightning/Rumble of Thunder Possible Overnight As Better Forcing Moves Through Area

December 15th, 2014 at 10:48 pm by under Chad's WLFI Weather Blog

As wind turns more southwesterly tonight, temperatures should remain steady, if not rise a bit more.

Showers will be the rule & if it is not raining, it will likely be drizzly with fog.

There is some better forcing in eastern Illinois moving northeastward, so I actually would not be surprised to see a flash of lightning/rumble of thunder tonight.

There are pockets of K-index in the 30s in northern Illinois & southern Indiana.  This index accesses largely elevated t’storm potential.

K Index is as follows:

K Index = (Temperature at 5,000 – Temperature at 20,000) + (Dew Point at 5,000 – Difference in Temperature & Dew Point at 12,000′)

Such pockets of K index may give us enough static with the forcing to promote electrical discharge as a flash & then rumble.

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The ’87 Bombogenesis

December 15th, 2014 at 9:43 pm by under Chad's WLFI Weather Blog

The 1987 December bomb was historic in the Midwest for its extreme pressure fall, wind gusts, historic blizzard & tremendous thunder & lightning with the snowfall in Illinois.  Snowfall & winds to near hurricane-force in Illinois resulted in a white-out.

It was this storm that really got my interest going in weather.  I won’t forget it.  We awakened to a completely pitch-black house, as we had lost power.  I remember clear as day my dad opening the door on our back porch about 8:30 a.m. (we had no school because of the wind & power outages) & the wind had entire large trees bending & in motion.  That memory of sustained winds at 40 with gusts to 60 mph led to a life-time interest in weather & climate that continues to this day.  I had never seen the trees in such frightful motion & such a howl for so long.

The sky had an odd greenish/gray hue & it was warm.

I have other memories at a younger age, from an intense 1984 storm to getting under the couch for Tornado Warnings in March 1986, this is my first really vivid, detailed recollection of weather.  From this point onward, my weather memories are highly-vivid & intense.

Storm bombed to Category 2 hurricane strength in a matter of 12 hours from subtle surface low in Texas to the monster in Illinois.  However, it was still impressive in Texas with up to 30″ of snow near El Paso.  A similar thing happened nearly the same time in December 1875, oddly, with an extreme surface low bombing in Illinois with wind here & snow from Texas to Michigan.

In our area, winds gusted to 70 mph with sustained winds near 50 mph at times.  Many trees & power lines were knocked down & power outages were widespread.

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The roar & motion of the trees I remember was similar to this:


A Look Back at the Warmest December On Record (& Second Warmest Winter On Record)

December 15th, 2014 at 3:16 pm by under Chad's WLFI Weather Blog

1889-90 was second only to the 1875-76 winter for warmest on record for our area.  December 1889 was the warmest on record in the Lafayette/West Lafayette data set with the mean temperature an incredible 15 degrees above normal!  The daily high mean was an amazing 17.5 degrees above normal!

January was similar, as was February, before the coldest air of the “winter” arrived in March (along with the heaviest snowfall of the season, but even that cold spell was rather short-lived & March still ended up substantially above normal.

A tornado struck Wayne County, Indiana with a track a half-mile wide & at least 4 miles long west of Cambridge City on December 11, 1889.  Damage was conducive to EF2 strength, it appears.

A severe weather outbreak occurred on New Years Day 1876 & several tornadoes hit areas south of modern-day Interstate 70 in January 1890.  Brazil, Terre Haute & many portions of southern Indiana reported significant damage.

In the other warm winter, a violent, potentially EF4 tornado, demolished part of Princeton, Indiana in February 1876 & another tornado struck southwest of this location in March 1890.

Louisville, Kentucky was struck by a very destructive tornado in March 1890.

Here, at least some severe t’storms occurred in the viewing area each month in the 1889-90 winter.

On the other side, the Pacific Northwest had its coldest winter on record with deep snows to the Oregon & Washington coasts.

Below is data from West Lafayette Purdue Experimental Farm, December 1889.

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Temperature deviations & surface low tracks for December 1889 (courtesy of NOAA):

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Check out this article on the opposite end of the spectrum the country in the 1889-90 winter:

http://www.siskiyous.edu/library/shasta/documents/hardwinter.pdf

Nevada City, California after a series of record-breaking snowstorms in 1889-90 winter:

(Courtesy of http://yubanet.com/index.php)

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Showers Moving In

December 15th, 2014 at 1:48 pm by under Chad's WLFI Weather Blog

First band of showers is moving into the viewing area as the California system pivots through northwestern Missouri.

Rainfall amounts still look rather insignificant with total amounts of 0.25-0.40″ by later tomorrow.  With the showers will be fog & drizzle mixed in, as well.

After lows tonight only in the 40s, highs tomorrow will run 47-51 by noon, then fall to 38-44 by late afternoon.

The wind will crank up tomorrow.  Southwest wind at 10 mph in the morning will give way to southwest, then west-southwest to west winds tomorrow noon-afternoon at 20-30 mph.

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Below is suggested forecast guidance regarding snowfall & the two systems generally around December 20-22.

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Holes In Overcast!

December 14th, 2014 at 2:04 pm by under Chad's WLFI Weather Blog

We are getting holes in the overcast in parts of the area!

Temperatures are running 47-54 as of 2 p.m.

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