Category Archives: 7-Day Outlook

Cold Close To The Week…

Screen Shot 2015-12-17 at 10.28.39 PMHighlights:

  • Cold with flurries; scattered snow showers to close the work week
  • Dry weekend ahead
  • Mild, unsettled Christmas week

Well that was a nice dose of reality across the region Thursday as temperatures remained in the lower to middle 30s with a gusty breeze in play all day.  Even a few flurries were reported across the northern ‘burbs Thursday.

Today will be colder and more blustery with scattered snow showers, particularly across the northeastern portions of the state, downwind of the Lake.  Elsewhere, even folks across central IN can expect a snow shower Friday afternoon/ evening as upper level energy teams up with arctic air.

Friday's 500mb chart shows upper air energy around to ignite scattered snow showers. Source: NCEP
Friday’s 500mb chart shows upper air energy around to ignite scattered snow showers. Source: NCEPCold air will be with us both Friday and Saturday, with highs in the lower to middle 30s both days.

Cold air will be with us both Friday and Saturday, with highs in the lower to middle 30s both days.

High resolution NAM highs for Friday. Source: Weatherbell.com
High resolution NAM highs for Friday. Source: Weatherbell.com
High resolution NAM highs for Saturday. Source: Weatherbell.com
High resolution NAM highs for Saturday. Source: Weatherbell.com

While forecast models continue to disagree on the timing and nature of the cold behind our Christmas week storm system, one thing is for sure and that’s that we think the majority of Christmas week will be milder than normal and rather unsettled.  Forecast models are in more agreement now than they have been, but we still note some considerable differences at this point.  The basis of our forecast next week is a blend of the GFS, GEM, and ECMWF, with a little more emphasis on the GFS/ GEM combo.  Regardless, don’t be surprised if you see some adjustments to the Wednesday-Christmas Day period as time draws closer.

7-Day Outlook, Christmas/ Thanksgiving, Forecast, Rain, snow, Unseasonably Cool Weather, Unseasonably Warm

Brief Shot Of Arctic Air Coming…

Screen Shot 2015-12-15 at 7.37.44 AMHighlights:

  • Hoping for PM sun
  • Scattered showers midweek
  • Snow flurries/ showers to end the week
  • Warm Christmas week ahead

We’re rumbling closer to Christmas with each and every passing day.  Thankfully, for the most part this week, weather will be nice for shoppers and early travelers.  Two systems of note are slated to impact the area this week- a band of scattered showers will move through here with a frontal boundary Wednesday. Secondly, upper level energy will team up with a shot of arctic air to provide a flurry/ snow shower opportunity Friday.

The 500mb chart Friday shows upper level energy capable of producing Friday flurries/ scattered snow showers. Source: NCEP
The 500mb chart Friday shows upper level energy capable of producing flurries/ scattered snow showers. Source: NCEP

Unfortunately for you winter lovers out there, the cold coming will leave about as quickly as it arrives.  We’re back to a warm and moist SW flow early next week that will lead to more unseasonably warm temperatures Christmas week (new possible records may be set), along with showers returning to our forecast as early as Monday.

Warm and wet weather returns early next week. Source: Weatherbell.com
Warm and wet weather returns early next week. Source: Weatherbell.com
7-Day Outlook, Christmas/ Thanksgiving, Forecast, Rain, snow, Unseasonably Warm

Record Warmth Coming; Rain And Storms As Well…

Screen Shot 2015-12-09 at 7.13.26 AMHighlights:

  • Warmth is the big story now
  • Showers and t-storms increase

Relatively quiet weather remains in the near-term period.  A fast moving disturbance will cross the state this morning and could spark a light shower or sprinkle, but we’ll get back to increasingly sunny conditions this afternoon and evening.

Moisture will begin to return as we close the week and head into the weekend, but it’s really not until the second half of the weekend that we begin looking at more widespread rain.

As a SW flow begins to transport Gulf of Mexico (GoM) moisture north, a light passing shower is possible Friday evening and Saturday.

Friday

Saturday

Despite the increase in cloudiness and threat of a passing shower, it won’t keep us away from flirting with records Saturday, and note the widespread portion of the Tennessee and Ohio Valley that will also be in jeopardy of setting new records.

Source: Weatherbell.com
Source: Weatherbell.com

Much better rain and storm chances ramp up Sunday afternoon into Monday.

PWATs (precipitable water values) increase dramatically during the aforementioned time period and could help fuel locally heavy rains during that time period, particularly with embedded thunderstorms.

PWAT

Cooler air will arrive early next week, but remain significantly above normal.  We’ll discuss the longer range a bit later…

7-Day Outlook, Forecast, Forecast Discussion, Forecast Models, Heavy Rain, T-storms, Unseasonably Warm

What Season Is This? Active Pattern Develops…

Screen Shot 2015-12-07 at 7.31.39 AMHighlights:

  • AM fog gives way to sunshine
  • Another fast moving disturbance moves through Tuesday night-Wednesday
  • Major warmth
  • Stormy finish

A quick glance at the updated 7-day shows two things, a lack of cold air and a rather active time of things.  In the near term, it remains a relatively quiet period.  We’ll deal with morning fog in spots this morning (especially north-central IN) and another fast moving disturbance in the Tuesday night-Wednesday time frame.

The big story as we move into the back half of the week is the unseasonably warm regime that will have many asking “What season are we in?”  We’ll aim for the upper 50s Thursday, around 60 Friday, and upper 60s Saturday as a strong SW flow develops in advance of our next storm system

Warmth will reach it's peak Saturday. Source: Weatherbell
Warmth will reach it’s peak Saturday. Source: Weatherbell

While a scattered, fast moving, shower is possible Saturday, the big story will be the warmth and a gusty SW breeze.

Our storm system will grow closer Sunday and we’ll ramp up rain and storm chances accordingly during that period.  Our two most trusted global models handle things differently as we progress into the Sunday-Monday time frame (strength, track, and timing), and we’ll need to continue to fine tune that particular period as we move forward.  As it stands now we’ll forecast rain and thunderstorms to become widespread Sunday before colder air arrives on the backside of the storm. Stay tuned.

SundayMap

MondayMap

7-Day Outlook, Forecast, Forecast Discussion, Forecast Models, Rain, T-storms, Unseasonably Warm, Windy

Happy Weekend…

Screen Shot 2015-12-04 at 10.01.21 PMHighlights:

  • Freezing Fog
  • Tracking Two Upper Air Disturbances
  • Mild Finish To Next Week

In the short-term, “dirty” high pressure will remain in control of our weather as we welcome in the weekend.  We label this a “dirty” high as a local inversion has resulted in plenty of low clouds and fog over the past couple days, despite high pressure being overhead.  Unfortunately,  the weekend will get off to a similar gloomy, foggy start.  With temperatures below freezing overnight and Saturday morning, areas of freezing fog can once again be anticipated.  Take it slow if you must be out and about early Saturday.  We keep our fingers crossed that we’ll be able to mix things up just enough to allow for at least some sunshine come afternoon.

The upcoming week will feature two upper air disturbances tracking across the state.  One comes Monday and the second arrives Wednesday.  Both will offer up an increase in cloudiness and a light shower chance.

Monday's 500mb chart shows the first of two upper air disturbances set to cross the state. Source: NCEP
Monday’s 500mb chart shows the first of two upper air disturbances set to cross the state. Source: NCEP
Another upper air disturbance will offer up shower chances Wednesday. Source: NCEP
Another upper air disturbance will offer up shower chances Wednesday. Source: NCEP

Once we get to late next week, a southwesterly air flow will take control and pump unseasonably warm air into the Mid West and Ohio Valley.  The mild air will be out ahead of an approaching storm system next weekend and we still anticipate changes as we progress into mid month…

7-Day Outlook, Forecast, Freezing Fog, Rain, Unseasonably Warm