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Winter Returns…

January got off to a frigid start.  Remember this coast-to-coast cold, including sub-zero temperatures across central IN, during the first week of the month?

t0-1024x818After the past week to ten days, that frigid open to the month seems like forever ago!  The past 7-10 days has featured a significant January thaw, and temperatures now, MTD, are warmer than average across the Ohio Valley.  Warmest anomalies can be found across the southeast region.

conus_mtd_t2max_anom_2017That said, the pattern is shifting back to winter for the last week of the month and while the duration, longer-term, can be argued, the next 2-3 weeks appear to offer an opportunity to play “catch up” in both the snow and cold departments.  Note the developing eastern troughiness.  This will bring colder air back into the east as we close January and open February.  The GFS ensembles, courtesy of Tropicaltidbits.com, also develops an interesting “blocky” look towards the end of the period in Week 2.  Should this verify, it would lead to a better chance of the cold, active pattern locking in.

GEFS2wk12417
You’re corresponding temperature anomalies show the shift back to a colder than normal regime.

Days 2-6
Days 2-6
Days 4-8
Days 4-8
Days 6-10
Days 6-10
Days 12-16
Days 12-16

A fast northwest flow will also result in multiple “pieces” of energy rotating southeast and we’ll forecast a period of snow showers by mid and late week, continuing into the weekend.  There’s the chance of a stronger clipper system sometime in the Sunday-Tuesday time frame that we’ll have to keep a close eye on.  We want to stress that global modeling will struggle with the specifics (timing and strength) of these clipper systems until within a couple days.

Longer term, while confidence is high on the evolution to a cold, wintry regime through the medium range, the longevity and sustainability of the cold is in question.  For instance, by Day 10 (as the GFS continues to drill cold into the region), the European ensembles are much less impressed and suggest the overall transient pattern we’ve dealt with for the balance of the winter continues:

ecmwf-ens_z500aNorm_namer_11

ecmwf-ens_T850a_namer_11Thinking here at IndyWx.com believes the European is likely rushing the warmer central look.  Time will tell…

**We do note the NEW European Weeklies lock a period of cold into the east from mid-February through early March, including a stormy (snowy) look.  Will Old Man Winter have the final say?

Updated 7-day later this evening!

Ensemble Discussion, Forecast Discussion, Forecast Models, January Thaw, snow, Unseasonably Cool Weather, Unseasonably Warm, Weather Rambles

Foggy Start; Winter Returns…

Screen Shot 2017-01-23 at 7.15.25 AMHighlights:

  • Dense fog this morning
  • Turning much colder this week
  • Scattered snow showers late week

Low Beams On…Dense fog engulfs most of central IN this morning.  Make sure you have the low beams on this morning as you head off to work and school and allow extra time.  A shower is possible at any point today, but particularly across the eastern half of the state.

Our next storm system will push through mid week.  Southwest winds will increase Wednesday and scattered showers will accompany a cold front moving through the state.  Temperatures will fall Wednesday night into Thursday and scattered snow showers will develop.

The theme late in the week and for the weekend will be a wintry one.  Upper level energy will interact with the colder conditions and result in scattered snow showers from time to time into the weekend.  The active northwest flow will remain into next week, as well, and we’ll have to keep a close eye for the prospects of a more “robust” clipper impacting the region just beyond this forecast period.

Upcoming 7-Day Precipitation Forecast:

  • Snowfall: Dusting – 1″
  • Rainfall: 0.10″ – 0.25″
7-Day Outlook, Fog, Forecast, Rain, snow, Unseasonably Cool Weather, Unseasonably Warm, Windy

Spring-Like Weekend, But Changes Loom…

Screen Shot 2017-01-20 at 10.25.29 PMHighlights:

  • Spring-like weekend
  • Unsettled times continue
  • Winter returns

Rare January White Leg Alert…The big news this weekend will be temperatures close to 30 degrees above normal and a legitimate spring feel.  Average highs across central IN this time of year are in the middle 30s and temperatures this afternoon will zoom to the lower-middle 60s.  Patchy morning fog and drizzle will be with us, but we’re remaining optimistic we could squeeze a couple of looks at the sun during the day.  Count yourself lucky if you do, indeed, see that weird giant bright thing in the sky! 😉

A developing storm system will track east across the central Plains and into the TN Valley this weekend.  This will result in a significant severe weather outbreak across the south and increasing rain chances here for the back half of the weekend.  The magnitude of the rain and potential embedded storms remains in question, but shower chances will at least be on the increase Sunday afternoon into the evening.  We note short-term, higher resolution modeling hitting the locally heavy rain threat harder than global data early this morning (centered on Sunday evening) and we’ll keep a close eye on things as most central IN communities remain waterlogged.  Winds will increase Monday- NE shifting to the N and gusts to 40 MPH with leftover showers continuing.

Tuesday will present a bit of a break in our active pattern before a fast-moving cold front blows into town Wednesday with scattered showers amidst blustery conditions.

We turn colder (you knew this incredibly mild pattern had to break at some point) late week and upper level energy will help ignite snow showers with the return of the wintry feel Thursday into Friday.

Upcoming 7-Day Precipitation Forecast:

  • Snowfall: Dusting – 1″
  • Rainfall: 0.50″ – 0.75″
7-Day Outlook, Forecast, Forecast Models, January Thaw, Rain, snow, Spring, T-storms, Unseasonably Warm, Windy

Times Are Changing, Or Are They?

January-to-date is running milder than normal across the region- to the tune of 3.3 degrees (F).  This is after a frigid open to the month, as you recall.

conus_mtd_t2max_anom_2017The second week of the month warmed significantly and continues, overall, for the next week.

ncep_cfsr_noram_t2m_week_anomThe mid-January warmth is attributed to a roaring PAC jet which is currently helping flood the country with temperatures much more like spring than the dead of winter.  We continue to forecast 60+ this weekend across central IN.

Winter lovers, have no fear as changes appear to be in the offing as we go through the last few days of January and head into February.  The winter so far has featured conflicting signals that continue to try and compete with one another to take hold of the pattern.  Can we get these drivers to align in a way that would pull a more persistent trough into the east for the second half of the winter and, ultimately, set-up a sustained cold pattern helping make up for lost time in the snowfall department?  Time will tell, but we do note the following late month:

  • (+) PNA pattern
  • Sudden stratospheric warming event
  • High latitude blocking

All are encouraging for a shift back towards a wintry regime.  As always, the devil is in the details and we’re skeptical as to the longevity of these signals.  “Cautiously optimistic” would be the way to sum up our current feel longer-term into the month of February, but we’re not as bullish on lock and hold cold, wintry conditions at this time as what you may hear from some of our national compadres.  Understanding that various drivers can have a different impact mid and late winter as opposed to early is one thing.  It’s also important to note that long term modeling has been abysmal as of late and we want to tread through the next couple of weeks with caution to see whether or not the cold drivers can finally take hold.

Needless to say, at least through late month, one can see the significant changes take place at 500mb.

Thursday:

ecm_eps_z500a_noram_2This Weekend:

ecm_eps_z500a_noram_5Next Thursday:

ecm_eps_z500a_noram_9Next Weekend:

ecm_eps_z500a_noram_11The pattern begins in the short-term with a look that will power anomalous warmth through the weekend, along with renewed rain chances Thursday night into Friday (another 1″+ for most), but begins to shift next week towards the colder look.  The 2nd (weekend) storm system will be significant and poses a severe risk to the southeast region.  Modeling has backed away on the heavy rain threat Sunday, but showers will be around early next week along with very windy conditions (40+ MPH gusts).  Blocking is forcing the low south.  By the time we get to next weekend, the pattern has done a 180 and in a position to drill unseasonably cold air back into the central and eastern portions of the country.

As far as storms go later in the period, it’s far too early to discuss specifics, but the pattern seems to be one that will promote the chance to get into the act on high-ratio producing clippers.  It’s the first time we can say that this year.  Time will tell…

10-day, Arctic Cold, Forecast Discussion, Forecast Models, Heavy Rain, High-latitude Blocking, PNA, snow, Spring Tease, Unseasonably Cool Weather, Unseasonably Warm, Windy