What a wild ride in the weather department.
You can't rely on anything more than 3 days out. A week to ten days ago all the data suggested that February was going to be warm and above average in temperatures. A week before that the data suggested that the polar vortex would arrive last week. Now it looks like the polar vortex is set to arrive next week but that could also change. Keep an eye on your weather apps but don't trust them past the third day. Here is the latest analysis from the National Weather Service office out of Indianapolis:
.SHORT TERM /Tonight through Wednesday Night/... Issued at 224 AM EST Mon Feb 1 2021 Strong subsidence throughout the short term period will keep conditions dry as a broad area of high pressure overtakes the central U.S. The ridge axis is progged to be over the Plains by tonight, shifting eastward throughout the short term period and eventually reaching the Great Lakes Region on Wednesday night. The strong northerly winds will persist into tonight with gusts up to 25 mph, but the gradient will begin to relax a bit by Tuesday. The northerly flow will help keep temperatures below normal though for most of the period with lows dipping into the teens and 20s tonight and Tuesday night, and daytime highs only topping off in the upper 20s to mid 30s on Tuesday. However, as the surface flow becomes southerly on Wednesday, a brief warming trend will commence. Daytime highs on Wednesday will top off in the low to upper 30s with slightly warmer temperatures in the low to upper 20s on Wednesday night. && .LONG TERM /Thursday through Monday/... Issued at 258 AM EST Mon Feb 1 2021 The long term will focus on two features, helping produce precipitation on Thursday and then sub-seasonal temperatures next weekend. A low pressure system will begin to develop in the lee of the Rockies Wednesday, moving eastward along a neutrally oriented upper level trough. Primary cyclogenesis will be within the left exit region of a 400-300mb upper level jet. The lack of significant advection and dynamic alignment should keep this system rather mundane. However, an influx of moisture out ahead of the trough will help invigorate precipitation development slightly, with overall QPF totals expected between 0.25"-0.5" over central Indiana. P-type should mostly be rain as central Indiana is located within the warm sector, although some mixed precipitation during onset is possible. Further into the period a majority of ensemble members are in decent agreement, especially for 150+ hours out, indicating strongly below seasonal temperatures next weekend. A positively tilted mid to upper level trough will reinforce the the southward progression of an arctic airmass into the eastern half of the CONUS. This is supported by a strongly negative AO depicting weak inertial stability of the polar jet. Given this combination of factors, confidence in a cold snap during days 6 through 7 is trending upwards. Current ensemble means are showing 1000-500mb thickness values below 4900 indicative of an extremely cold air mass. Although, exact temperature values are hard to predict and will vary as models ingest observations in the coming days. Overnight lows on Saturday night are expected to be in the single digits, but below zero values are not out of the realm of possibilities.
Next Wednesday's low temperature will be 35 degrees, not -20 degrees.
Mistakes. They happen.
.SHORT TERM /Saturday through Sunday night/... Issued at 358 AM EST Fri Jan 29 2021 A strong upper low pressure system will swing out of the plains and northeastward toward Missouri and then Illinois on Saturday/Saturday night. Initially this system moves quickly and the trough is negatively tilted, but as it arrives in the mid Mississippi valley it slows down, straightens up and flattens out, and from there on its motion is very slow across the Ohio valley. The surface low spends Saturday night to Sunday night tracking from western Illinois across southern central Indiana to Ohio. Strong isentropic lift will develop on Saturday afternoon ahead of the low, and a low level jet will provide ample lift and moisture transfer ahead of the low. Still some uncertainty regarding how far north the warm air gets Saturday night on the nose of the low level jet, and this will have a large impact on which areas get rain or a rain snow mix versus snow. That said, models have come into good agreement on the track of the low, if not great agreement on the thermal profiles. Very strong lift will be in place Saturday evening/Saturday night with the aforementioned isentropic lift along with good q vector divergence aloft. With the track of the 700 mb low right across central parts of the area as well, looks like the band of heavy snow could include northern/northeastern counties. With this in mind and potential for 6 plus inches of snow over the northern/northeastern counties, issued a Winter Storm Watch for that area. Also of note, snow should be of the heavy and wet variety, and there is some potential for 30 mph wind gusts to come along with it. Central and southern parts of the area are more likely to get into that warm nose and see enough warming that changeover to a mix and then rain could be pretty quick Saturday night, and thus left the rest of the area out of the watch. Sunday during the day, the surface low tracks slowly enough that warming will be in place for most of the day and expect precipitation to be mainly rain, with the possible exception of the northernmost counties. By late Sunday afternoon, though, the low should be over Indiana or moving just east, allowing some of that cold air to move back in behind it. This should bring a change back over to snow. Since the system is moving so slowly, there is still plenty of forcing from the upper system over us. Thus keep chances for snow going through Sunday night, with wraparound potential lasting into Monday morning. While there is some chance for accumulating snow to ramp back up a little Sunday evening, the event will likely be diminishing at that point as forcing weakens and moisture is cut off. Could wind up seeing total precipitation amounts over an inch across the area given the setup and moisture. With things being relatively dry though and streams running well below normal, should be able to handle this moisture without widespread flooding issues. && .LONG TERM /Monday through Thursday/... Issued at 350 AM EST Fri Jan 29 2021 While the progressive mid-level pattern for the period will perhaps exhibit more amplification than earlier this winter, when some of the southern-stream systems` circulations wholly cut-off from the northern jet...true arctic air will still be very much absent from the northwest flow entering Indiana Monday morning. Nevertheless, following any last snow showers that should taper off during the day Monday...the approaching surface high will bring near to slightly- below normal temps to start the work week. Residual considerable cloudiness will likely linger Monday from the departing winter storm`s last lobe of troughiness. Upper level ridging will then join the surface ridge`s building-in amid the mid-level`s greater amplification...providing a decently pleasant-for-mid-winter Tuesday-Wednesday, featuring lighter winds and partly to mostly clear skies. Moderation should follow around the Wednesday time frame courtesy southeasterly flow as the surface high drifts to the east. Attention will soon thereafter turn to the next mid-latitude storm that will be coming out of the Rockies. Some disagreement exists on how fast this next system deepens at the surface, although there is at least moderate confidence its central pressure drops significantly by late Wednesday over the central High Plains, before tracking a good ways to our region`s west on Thursday. Guidance is indicating this system`s wave may actually tap into at least a piece of arctic air by late week, although this detail will be hammered out in the days to come. For central Indiana, progged to be on the system`s generally warm side, southerly breezes should provide an ample ribbon of Gulf moisture. The storm`s cold front will focus at least chances of rain, or mix-to-rain Thursday. Temperatures for the period through Wednesday are expected to range from morning lows in the ~20F realm, while afternoon highs slowly moderate through the 30s for most locations. Wednesday night- Thursday is expected to feature readings well above normal.
#BOTS FANS!
It's wasn't even a big snow but it was fun to watch. I think we got about three inches. Enjoy!
I think winter is over for us.
We have one more shot at snow tomorrow night into Thursday morning. After that it warms up and next week is the very short month of February with only 28 days.
Wednesday's high temperature will be 33 degrees with a 30% chance of snow. It will not be a great day to go golfing.
#BOTS
#BOTS Update: 1 Week left
If we don't get any snow by January 28th or by next Thursday then winter is about over. That doesn't mean it won't snow again because we can see snow here as late as April. What it means is that the cold air will start to retreat and our chances of seeing a big snow storm will go down.
#BOTS
The snow gods favor us today! #BOTS!
How lucky could we be? There will be a very thin stripe of snow coming tonight. It will cover about 13 counties in the southern part of the state and ours is one of them. #BOTS!
From the National Weather Service
Special Weather Statement
Special Weather Statement National Weather Service Indianapolis IN 607 AM EST Fri Jan 15 2021 INZ021-028>031-035>049-051>057-060>065-067>072-152130- Carroll-Warren-Tippecanoe-Clinton-Howard-Fountain-Montgomery- Boone-Tipton-Hamilton-Madison-Delaware-Randolph-Vermillion-Parke- Putnam-Hendricks-Marion-Hancock-Henry-Vigo-Clay-Owen-Morgan- Johnson-Shelby-Rush-Sullivan-Greene-Monroe-Brown-Bartholomew- Decatur-Knox-Daviess-Martin-Lawrence-Jackson-Jennings- Including the cities of Delphi, Flora, Williamsport, West Lebanon, Lafayette, West Lafayette, Frankfort, Kokomo, Attica, Covington, Veedersburg, Crawfordsville, Lebanon, Zionsville, Tipton, Fishers, Carmel, Noblesville, Anderson, Muncie, Winchester, Clinton, Newport, Rockville, Greencastle, Plainfield, Brownsburg, Danville, Indianapolis, Greenfield, Cumberland, New Castle, Terre Haute, Brazil, Clay City, Spencer, Martinsville, Mooresville, Greenwood, Franklin, Shelbyville, Rushville, Sullivan, Linton, Bloomfield, Bloomington, Nashville, Columbus, Greensburg, Vincennes, Washington, Loogootee, Shoals, Bedford, Mitchell, Seymour, Brownstown, and North Vernon 607 AM EST Fri Jan 15 2021 ...Briefly Intense Snow Showers or Squalls Likely Later Today and Tonight... Scattered snow showers are expected to develop during the course of the day today, and from the midday hours into the evening hours, some of these snow showers may become intense or squall like in nature, with briefly intense snowfall rates, severely reduced and rapidly varying visibilities, and slick spots developing on roads and other surfaces due to minor snow accumulations. If traveling today and tonight, be alert for the potential for these hazards, and if encountering them, drive carefully. Slow down and increase distances between vehicles until conditions improve markedly.
I think "Snow Squalls" are worse than blizzards.
Why? Because Blizzards come with warnings for a particular geographical area. Snow squalls are like severe storms and tornadoes in April. It's will be sunny one minute and then the clouds will turn dark and then a storm is upon you. That's exactly what snow squalls are like. You never see them coming and once it happens, there's wind driven snow and blinding white-out condition for 15 minutes. After that, the sun is out and you think it's over except it's not. Blizzards allow you time to prepare. Snow squalls do not because they are random. Here is what the National Weather Service office from Indianapolis is saying:
.SHORT TERM /Friday and Friday Night/... Issued at 314 PM EST Thu Jan 14 2021 Forecast challenges focus on a growing confidence in a potential high impact convectively induced snow shower/squall setup for Friday afternoon and evening as the upper low drifts across the region. The upper low will track slowly east through the period from western Illinois to eastern Indiana with a weakening surface reflection following in tandem. The presence of both features will produce an increase in forcing aloft over the region that is set to peak during the afternoon and evening hours. The real story though is set to unfold at the mesoscale level within the thermodynamic structure of the low levels where parameters are set to align to provide potentially the best convective setup for snow showers experienced locally within the last 2 years or so. High confidence exists in potential localized travel impacts throughout the afternoon and evening hours Friday. Scattered snow showers are possible through the morning and will largely focus over northern counties. After 18Z though is when the atmosphere will start to set up nicely for the convective threat as the upper low moves into the area. Model soundings are extremely impressive in the 18-00Z timeframe in support of heavier bursts and snow rates within showers and developing squalls. Dry adiabatic flow is set to peak at a level up to 700mb with weak instability present through the boundary layer and steepening lapse rates that will peak at 8C/km or greater below 800mb and potentially in the 9-9.5C/km range in the lowest 2kft or so. Furthermore...the dry adiabatic layer will coincide with the dendritic growth zone by mid to late afternoon. This will result in an increasing coverage of snow showers with locally brief heavy rates of snowfall that may approach meeting snow squall criteria over a 3-5 hour period focused from mid afternoon into the early evening. Have increased pops substantially over guidance for the afternoon and continued it through Friday night. While the convective component will diminish Friday evening...the presence of the upper low and surface wave over the region will maintain strong forcing aloft to keep snow showers going most if not all of the night. CAMs analysis is picking up on the localized...convective nature of the showers and the very likely possibility that those locations that get under any repeated bouts of brief heavy rates of snowfall will likely cash on some light accumulations potentially up to an inch or greater by Saturday morning. The greatest concern with the upcoming snow showers for Friday afternoon and evening is the potential impact to travel and roads across the region due to the quick hit and miss nature of locally heavy snow bursts. One potential saving grace which may mitigate concerns to some degree is that surface temps during the afternoon in particular are likely to fall in the 32-36F range but if it snows hard enough even for a short time at these temperatures...expect road to become snow covered and slick in spots. As temperatures fall Friday night...this could cause an increase in icy conditions as well. Will continue to message concerns via HWO and social media platforms at this time. Temps...undercut guidance across the board for highs Friday which look far too warm. Expect highs to hold mainly in the mid to upper 30s. Lows will fall back into the upper 20s Friday night which will end up above most guidance as well. && .LONG TERM /Saturday through Thursday/... Issued at 234 PM EST Thu Jan 14 2021 An active pattern continues into the long term period as we transition into being along the backend of the exiting strong upper level low pressure system. During the day Saturday, surface winds will generally be westerly with some mid and upper level advection of Lake Michigan air into the northern counties. Isolated to scattered snow showers are expected through the day with the best chances mid afternoon when soundings show good low level lapse rates and a passing vort max. The best forcing will have already exited so with meager moisture, only a few tenths of an inch of snow are expected along with some locally higher amounts where snow behaves more convectively. Going into Saturday night, confidence in precipitation drops off as a strong low level inversion builds. There are some signs that there could be some freezing drizzle as moisture aloft drops off and a lack of ice crystals is present in the cloud deck. The big question will be if there is enough low level lift to lead to any precipitation and confidence in that is too low at this time. 0 During the day Sunday, another upper level low will be arriving from the west triggering another round of isolated to scattered snow showers during the day and into the overnight hours. Upper level forcing is strong with this system, but like the last the low level moisture is lacking which will limit the overall potential for snow accumulations. This pattern of isolated to scattered snow showers will continue into much of early next week, but confidence in timing for each of these and the impacts for central Indiana wanes later in the period as differences in model guidance increases along with the uncertainty with how each system will interact with the next. A stronger system approaching from the Gulf may bring some impacts to central Indiana as early as Thursday, but confidence is higher that impacts won`t be seen until Friday or Saturday and more likely closer to the Ohio River. Overall, light snow accumulations are expected this weekend with amounts between a half inch and an inch. With the convective nature of the snow on both Saturday and Sunday, locally higher accumulations with some areas of 2 inches certainly possible. Going into next week, occasional shots for a rain/snow mix are possible, but not as likely as the weekend system. Temperatures will begin the period near normal with above normal temperatures next week. &&
ICYMI - (That doesn't mean an "Icy Mi-chigan")
News reports are saying that the "Polar Vortex" will arrive next week. I agree but I don't think it will last long.
https://www.nationalgeographic.com/environment/2021/01/the-polar-vortex-is-coming-raising-odds-for-intense-winter-weather/
If we don't get any substantial snow between the 18th and 28th (a ten day span) then winter is pretty much done for us. All signals are on the table for an early severe weather scenario for February instead of March.
Stay safe.
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