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Category: Monthly Outlook
Permanent link to this article: https://indywx.com/long-range-update-cool-set-back-doesnt-last-looking-ahead-to-april/
Mar 11
Long Range Update And Summer Preview…
One more unseasonably chilly spell awaits late-March (behind our mid-March spring “tease”), but we continue to believe an unseasonably warm stretch of weather gets going by the last few days of the month- continuing into April. Furthermore, meteorological spring overall continues to look warm, relative to average, for central Indiana. In the event you missed our Spring Outlook earlier, it can be found here.
However, what follows the late-March set-back is a more significant and sustained push of unseasonably warm conditions.
Note the positive PNA that will help drive the chilly pattern next week returns to neutral as we put a wrap on the month:
To no surprise, modeling is painting a vastly different look as we close March and open April.
We turn cooler next week with the positive PNA in control, but this won’t last…
Note the significant change aloft (and at the surface) as we close the month and get set to head into April…
Longer term, modeling continues to give us an actual spring this year. We continue to expect average to slightly above average temperatures in April, complete with slightly above normal precipitation (with a “ramp up” in severe chances, locally).
Modeling is following suit with that idea:
It should also be noted that while not shown, the new European Weeklies in this evening also support the warmer than normal April idea.
As we look forward, we continue to research and build our summer outlook. Early indications would suggest that we transition out of an overall warmer than average spring towards a seasonal, to slightly below average, time of things this summer, complete with above normal precipitation. We, obviously, still have some time to go before the final product is ready to be published, but stay tuned. We are planning to launch our official summer outlook in early May.
Permanent link to this article: https://indywx.com/long-range-update-and-summer-preview/
Mar 06
Running the Gamut; Looking Ahead to April…
We’ll apologize in advance for the long-winded post tonight, but there’s a lot to cover. Not only do we have the accumulating snow on deck, a couple of strong storm systems this weekend into the middle of next week, but the long range pattern is set to turn cold (again) after a mid-month respite. We also want to look ahead to our early thoughts towards April…
Let’s take things one at a time:
Thursday-Friday Snow
While we don’t have major changes to our ongoing snowfall forecast, we have “sagged” the swath of 1″ to 3″ snow south just a hair given the latest computer model guidance. Steadiest snow should fall Thursday night into the predawn hours Friday. We’d anticipate a slick Friday morning commute through the heart of central Indiana.
Snow should exit off to the southeast around, or just before, lunchtime Friday. As always, your ground-truth reports are welcome (feel free to send to us on Twitter or via e-mail).
Warmer Side Of Things
The ‘mean’ trough position will shift to the west (temporarily) and lead to an overall milder time of things for the mid-month stretch. Unfortunately, the milder air will come with a wetter pattern.
This milder, wetter pattern will be highlighted by (2) storms:
I. Saturday, 3/10
II. Tuesday-Wednesday, 3/12-3/13
Both storm systems will be capable of producing locally heavy downpours and embedded thunder. Greatest chances of severe will remain south of central IN with this weekend’s storm, but may be further north next week. We’ll keep a close eye on things and issue Client Briefs if need be as we get closer.
A combination of the GFS and European computer models print-out rainfall totals between 1″ and 2″ over the upcoming 10-days and this seems reasonable given the fact both storm systems will be able to tap into Gulf of Mexico moisture.
From a temperature perspective, the brutal cold will come to an end behind our late week snowmaker. While “transient” chill will follow both of the upcoming storm systems, we’re heading into a much milder pattern, overall, through the mid-March stretch. Mildest air will come directly in front of the storm systems, highlighted by a couple of 60 deg. + days the middle of next week.
Positive PNA takes over
Unfortunately (for lovers of spring), the mid-month warm-up will be only a “tease” as we’re set to trend cooler, relative to normal, for the last 10 days of the month. The reason? A developing positive PNA.
To no surprise, we see the cooler pattern returning on the computer models:
Not only will we turn colder to close the month, but Thursday likely won’t be our last accumulating snow of the season…
Looking Towards April
Despite the late-March “set back” to a chilly time of things, we continue to think a more sustained “stick and hold” spring pattern looms around the corner. In fact, we agree with the latest CFSv2 delivering a warmer than normal pattern for April, as a whole, to the eastern portion of the country.
Note that as we go, the model is getting warmer for April with each passing day. As things stand now, we think the trough will pull back to the west with a more sustained ridge in place across the eastern portion of the country in April. With this, a wetter than average regime likely awaits, including an uptick in severe chances further north into the region.
Permanent link to this article: https://indywx.com/running-the-gamut-looking-ahead-to-april/
Feb 25
Frigid Open To March And Late Month Musings; Reviewing The NEW European Weeklies…
Average temperatures through the 1st (5) days of the month include highs of 46 F and a low of 29 F at Indianapolis. Instead, a frigid pattern will grip the region as we move through early March, including highs that will likely only top out in the lower to middle 20s and lows in the upper single digits to lower 10s as we move through the first week of the month (coldest centered on Sunday through next Wednesday).
Should we get any sort of snow down during the period (still up for debate as of this evening), lows will likely approach 0 F. The best opportunity for accumulating snow over the upcoming week would come Friday night into Saturday, but confidence remains low. Thereafter, we prefer the “suppressed” ideas currently portrayed by modeling as more meaningful winter storm threats impact the lower Ohio/ TN Valley and southern Appalachian region- especially with such an anomalously cold pattern in place.
Speaking of cold, the deep and expansive snowpack across the central and northern Plains won’t allow the late season taste from the arctic to modify as much as it may otherwise. As the frigid air mass settles southeast, below zero wind chill values are a good bet early next week across the northern half of the state. “Tap the breaks” on meteorological winter kicking off March 1st…
With that said, the NAO and AO are expected to remain positive and while initially “trumped” by the significantly negative EPO, this will trend positive by mid-month. These all suggest the cold is limited and that there shouldn’t be any change to the idea that we really begin to feel more spring-like by the middle of March. This is backed up by the continued idea that the MJO rumbles into Phase 4 by mid-March, as well (again argues for warmth).
Sure enough, longer range models show the ridging and associated warmer times ahead:
It should be noted that with the mean trough position taking up shop across the western portion of the country mid-March, not only should we moderate, but we should also see a return of wetter/ stormier times. With the GOM (Gulf of Mexico) running above normal, early season severe weather outbreaks will have to be closely monitored…
The new European Weeklies in this evening also back up the idea of an unseasonably cold 1st half of the month giving way to milder conditions by mid month. The model paints a drier than normal pattern over the Ohio Valley and Mid West over the next couple of weeks before wetter signals return by the middle of March.
Permanent link to this article: https://indywx.com/frigid-open-to-march-and-late-month-musings-reviewing-the-new-european-weeklies/
Feb 24
Potential Wintry Mischief Through Early March? Late Month Changes…
Top wind gusts today have reached 66 MPH at IND with numerous reports of downed trees and power lines throughout the northern half of Indiana.
As we look ahead through the upcoming week, a couple of rather minor systems may deal light precipitation to the area, but it’s what lies ahead next weekend that’s already drawing interest. Unfortunately, modeling is trying it’s best for a “repeat” high wind event next Saturday.
The overall setup is eerily similar as a rapidly strengthening surface low tracks northeast into the Great Lakes region. This setup would once again support 50+ MPH gusts.
With the pattern change underway at this point, colder air will be more readily available and backside snow may be more “meaningful” next weekend. That’s something we’ll be keeping a close eye on.
Winter weather enthusiasts will have a couple of weeks of at least being on the playing field for the possibility of late season accumulating snow, but it continues to look like that window closes quickly by mid-March as a true spring pattern takes hold.
For those who watch the operational data with each and every update (sometimes as much as 4 times per day)- tread with caution. While significant late season winter storms can result from such a pattern change that’s underway, it’s impossible to worry about specifics in this type of regime until within 4-6 days.
It would appear the pattern would support potential “fun and games” next Saturday, the 2nd, and possibly again in the March 5th-6th time frame.
Enjoy it while you have it, lovers of winter… Signals continue to point towards a significant shift to warmer times for the 2nd half of March.
Permanent link to this article: https://indywx.com/potential-wintry-mischief-through-early-march-late-month-changes/