Category: Unseasonably Warm

Iron Bowl Saturday: December Rambles…

This is a special day in the McMillan house.  Iron Bowl Saturday only comes around one day a year… Needless to say, the Auburn flags have been on the vehicles since Wednesday, we’re decked out in our orange and blue, and game faces are on for this evening’s matchup.  WAR EAGLE!

As we get set to flip the calendar to December, we wanted to post some latest thinking.

Let’s take a look at the latest teleconnections.  As we’ve been talking, there’s a lot of “noise” in model land, including conflicting signals.  The positive NAO and AO argue for warmer than average conditions, while the positive PNA suggests chillier than normal times should prevail.

We wanted to post the latest model predictions of each teleconnections, courtesy of Weatherbell.com.  Additionally, courtesy of madusweather.com, here’s what each teleconnection “phase” would normally lead to in December.

NAO

Screen Shot 2015-11-28 at 10.55.21 AMNAOpos_12dec

AO

Screen Shot 2015-11-28 at 10.55.07 AMAOpos_12dec

PNA

Screen Shot 2015-11-28 at 10.55.34 AMPNApos_12decSimply based on the teleconnections, you would build a December forecast that would lean more warm than cold, as the short term positive AO and NAO should trump the positive PNA.  As we look at the month, as a whole, the AO and NAO are forecast to trend more neutral, while the PNA remains solidly positive.  Does this suggest colder air, relative to normal, would invade mid and late month?  – Certainly something to watch.

Additionally, the latest Southern Oscillation Index (SOI), has begun to take a negative hit.  This is after weeks of positive SOI values- relative to the base state.

Screen Shot 2015-11-28 at 10.47.52 AM

 

 

 

 

While it takes a while to impact the pattern, locally, this negative hit does suggest mid and late month could be a bit more interesting from a wintry perspective.  We shall see.

The CFSv2 remains very consistent on a warm month, relative to normal, particularly across the northern tier.

cfs_anom_z500_noram_201512_w3cfs_anom_t2m_noram_201512_w3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

While we can’t post the European weeklies here, the latest run suggests colder, and stormy times around Christmas week.  Now, we should also note the overall performance of the Weeklies hasn’t been as accurate compared to normal over the past few months, but it’s another interesting trend to keep an eye on.

The MJO will begin the month in Phase 3 before going into the “wheel house.”  All-in-all, we don’t get a “hat tip” from the expected monthly MJO forecast, with the exception of Phase 3 to begin (warm phase).

EMON_phase_MANOM_51m_full

Screen Shot 2015-11-28 at 11.53.45 AMTo sum up:  Long range forecasting is always a gamble.  Only the good Lord knows what the future holds.  That said, there are times when we feel more confident about our long range, monthly outlooks, more so than normal.

We’ll lean warmer than normal for December (+ 1.5 at IND), and this really plays into our Winter Outlook (slow start expected with the emphasis on the cold and snow mid and late winter), but that doesn’t mean we’re expecting a “boring” month.  Keep in mind November has been both warmer AND snowier than normal, with a very busy 2nd half of the month.

We’ll have plenty of challenges to handle as we rumble through the month no doubt, but we expect the positive AO and NAO to trump the positive PNA to start to the month.  As we progress into mid and late month, we’ll have to be on alert for potential impacts of that significant SOI hit to open the month.  We’ll also keep the Weeklies in check to see if the colder, stormy look Christmas week remains.  It’ll be fun, as always.

To close, here’s one more emphatic WAR EAGLE from our home to yours! 🙂

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Nice Today Before Our Next Storm Arrives…

Screen Shot 2015-11-15 at 8.55.18 AMHighlights:

  • Beautiful Sunday
  • Clouds and rain return
  • Colder late week
  • Eyeing a potentially wintry end to November

Our next storm system is coming ashore along the West Coast this morning.  That storm will impact our weather this week, but today we’ll focus on the sunshine and beautiful conditions.  Temperatures will climb into the lower to middle 60s.  With what lies ahead, we’d highly suggest taking advantage of the nice weather today and finish up any of that outdoor work you may have.

Clouds will increase Monday and the initial surge of moisture will provide showers and light rain by afternoon and evening.  A strong southerly flow continues Tuesday into Wednesday with periods of rain.  It won’t rain the entire time, but more times than not.  A push of heavy rain still appears likely Tuesday night into Wednesday.

The image below is a look at forecast PWATs, thanks to Weatherbell.com, for Tuesday night.  When these values reach 1.5″-2″ that’s a good indication for very heavy rains.  We’ll continue to forecast widespread 2″+ type rainfall with this storm system.

gfs_pwat_conus2_14Once this next storm moves out, we’ll get back to drier and colder times to end the work week.  Attention will then shift to a colder, potentially wintry, end to the month, including the Thanksgiving holiday. It’s too early for specifics on storminess, but model data does hint at a storm of “interest” around Thanksgiving.  With colder air making a return, it’s certainly possible this next storm has a wintry component to it…

The latest GFS ensemble temperature anomaly chart shows the colder than average pattern setting in to wrap up November.

KIND_2015111500_nxa_384

Permanent link to this article: https://indywx.com/nice-today-before-our-next-storm-arrives/

Still Eyeing Mid Week Storms; Windy And Colder To Close The Week…

Screen Shot 2015-11-10 at 7.07.33 AMHighlights:

  • Wednesday night storms
  • Very windy to close the week
  • Colder Friday

The overall set-up over the next couple days will feature a strong autumn storm coming off the Rockies (today), crossing the Plains (Wednesday), and heading northeast into the Great Lakes to offer up some “fresh water fury!” (Thursday).

Here’s the track of our storm, courtesy of Weatherbell.com.

TueEvening

WedEvening

ThrEveningWe still need to monitor things closely for the potential of severe weather Wednesday evening, but latest data would suggest a lower chance of severe, overall.  Certainly not worth letting your guard down, but the lack of moisture return and timing are both on our sides in this particular event.  Localized damaging straight line winds are still of greatest concern of any of the severe elements across central IN and this would be for Wednesday night.

Here’s a look at the latest simulated radar for 10p Wednesday.  As we always say, don’t pay particularly close attention to the precise time.  This should be used as guidance as what the radar may look like Wednesday evening.

10pradarWedAs mentioned above, the speed, timing, and lack of moisture return strongly argue against significant rainfall with this storm.  We’ll forecast around 0.25″ with locally heavier totals in storms.  Not a big deal from a precipitation perspective.

What is a big deal is the wind on the backside of the low as northwest gusts really crank in the Thursday-Friday time frame (30-40 MPH).  Needless to say, Thursday isn’t a day to wear a hat. 🙂

Longer term, data continues to argue against any sort of sustained chill through the rest of November.  We note the SOI is actually positive right now.  This is certainly unusual with the ongoing El Nino and well above the base state (a warm sign).

Screen Shot 2015-11-10 at 6.55.51 AM

 

 

 

The MJO is also projected to rumble through the warm Phases of 2 and 3 over the next few weeks.  Note these are overall warmer than normal phases in November.

Screen Shot 2015-11-10 at 6.59.42 AM

 

 

 

 

 

 

 

 

 

 

 

 

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Permanent link to this article: https://indywx.com/still-eyeing-mid-week-storms-windy-and-colder-to-close-the-week/

Dry, Chilly November Weekend; Mid Week Storms…

Screen Shot 2015-11-07 at 10.56.54 AMHighlights:

  • Sunny and cool
  • Midweek Storms
  • Prolonged period of windy weather late week

High pressure is building into the Ohio Valley this weekend and helping supply sunshine and that cool, crisp air we enjoy this time of year.  Freeze and frost conditions are ahead tonight and again Monday morning as high pressure moves overhead and results in clear skies and calm winds.

As the high moves to our east, a return SW flow will help moderate temperatures for mid week. As our next storm system comes out of the Plains it’ll intensify as it tracks into the Great Lakes.  Thunderstorms will accompany the cold front as it swings through the state Wednesday night.  We’ll monitor for strong to severe storm potential.  A lot will hinge upon the precise track of the surface low and we’ll keep a close eye on things over the next couple days.  We’ll turn cooler again late next week with strong winds shifting from the SW to NW.

Upcoming 7-Day Rainfall Forecast: 0.50″

Permanent link to this article: https://indywx.com/dry-chilly-november-weekend-mid-week-storms/

Video Update: Chilly Weekend; Severe Potential Next Week…

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Permanent link to this article: https://indywx.com/video-update-chilly-weekend-severe-potential-next-week/