Happy Saturday afternoon to all! This evening’s video covers what continues to look like an active weather pattern, including multiple rain chances ahead for the upcoming week. We also discuss the upper air pattern and the expanding area of heat.
Category: Jet Stream Discussion
Permanent link to this article: https://indywx.com/2014/08/16/talking-heat-humidity-and-rain/
Jan 21
Historic Snow Season Keeps Rolling Along…
The winter of 2013-2014 is off to a rip-roaring start and, as we’ve discussed in previous posts, the mid to long range data suggests we remain locked in an exceptionally cold and snowy pattern. Officially, as of this evening, the Indianapolis National Weather Service has posted some impressive stats (the full report can be found here), including:
- Through Jan. 21st, the 24.4″ of snow ranks as the 3rd snowiest January on record.
- Through Jan. 21st, the season-to-date snowfall of 33.2″ ranks as the 2nd highest on record in the period Dec. 1st through Jan. 21st.
- Through Jan. 21st, the season-to-date snowfall of 33.2″ ranks as the 8th snowiest on record for an entire winter season.
As we look ahead to the upcoming 7-10 day period, we note a continuation of arctic reinforcements- each which will be plenty capable of adding to the snowfall total. Additionally, our cold air mass will only grow even more severe and bitter over time, including multiple days during the aforementioned period where central Indiana will go below zero. Finally, there have been many questions concerning a potential big storm centered on early February. I’m not sure where this rumor started, but it’s far too early to say with any sort of confidence any specifics around a possible big winter storm early February. That said, as we’ll get into briefly below, the pattern does appear to be aligning itself in a way where a widespread winter storm is possible somewhere across the eastern half of the country.
Okay, okay, back to the near term… Let’s start with tomorrow! After a cold and dry start to the day, our next arctic front will blow into the region during the evening. Arctic fronts are notorious for having bursts of heavy snow rates in a scattered fashion and this appears to be the case as the next arctic front moves through Wednesday evening. We bracket the hours of 5p-8p for the possibility of heavy snow bursts racing through central Indiana. While these won’t last long, they’ll likely be intense- capable of depositing a quick 1″-2″ of new snow on a gusty northwest wind within 30-60 minutes. White-out conditions and extremely heavy snowfall rates will accompany the heavier bursts of snow. Latest high-resolution model data shows the heavy snow bursts accompanying the arctic front tomorrow evening:
Thursday will be mostly dry and frigid, but all eyes will then begin to turn to our next significant winter event Friday into Saturday. The pressure gradient between high pressure across the Mississippi River Valley and the next approaching arctic front (and associated low pressure) will really being to kick up the wind across our region Friday. We’re afraid we deal with another round of severe blowing and drifting snow Friday, especially Friday afternoon and night. Areas most suspect to drifting and blowing snow will be central Indiana’s open country and may not be too different from the problems our region dealt with Sunday into Monday morning from blowing and drifting.
As we approach Friday night into Saturday, snow will overspread the region and will likely accumulate to the tune of a “few inches” during this time period. Strong winds will remain, shifting from the west to the northwest and eventually north. Open country will remain the prime place for continued severe blowing and drifting problems.
Just as soon as Saturday’s snow systems exits stage right, we turn our attention to potentially another significant snow maker for the second half of the weekend. Latest model data remains consistent on moving another potent clipper system into our region Sunday, including the GFS and Canadian forecast models. We still have time to fine tune the precise track of the storm, but just north of the low’s track an additional 3-5″ type snow is possible Sunday. Note the GFS and Euro in relative agreement on the track of the low, with the Canadian currently a touch further north. We’ll fine tune in the days ahead… Experience with similar patterns from the past suggests central Indiana should brace for more accumulating snow Sunday.
As for the brutal cold, we note multiple pushes of fresh arctic air behind each snow maker. We currently target Thursday morning, Friday morning, Tuesday morning, next Wednesday morning, and next Friday morning as having the most likely shot at dipping below zero. The “coldest of the cold” likely means Tuesday morning takes the crown, with lows potentially dipping into the double-digit below zero range for central Indiana. The European forecast model (below) even shows sub-zero temperatures making it as far south as the southern Appalachians.
As we look even longer term, there have been many questions centered on the potential of a big winter storm for early February. Before we go any further, we want to stress it’s far too early to make any claim of certainty to the above. That said, there are items we can pick up on to a least “raise an eyebrow” that something of significance may be brewing… Do we mean for anyone to take that verbatim and to the bank? Absolutely not.
The European Weeklies suggest we need to keep an eye on the first week of February. They show a potential phasing of the jet (where the northern and southern streams of the jet stream phase together- often times resulting in a big storm)… That said, we want to again stress this is far too early to be discussing with any sort of certainty. Heh, the next week will keep us busy enough!
Keep the shovel handy! Snow removal companies, thank you for your service and hard work…hopefully you have plenty of coffee on hand!
Permanent link to this article: https://indywx.com/2014/01/21/historic-snow-season-keeps-rolling-along/
Dec 23
Impressive Cold Pattern Looming; Beware Of The Northwest Flow…
We continue to be very impressed with the cold pattern that’s looming. Even before the warm up and thaw last week, we made mention that the seeds were being planted for a very cold close to December and open to 2014. Latest data continues to back this idea up. Additionally, in the longer term, there are some goings on that would suggest we better hunker down for a colder than average January. While December will finished colder than average, a colder than average January can really hurt the pocket book as “average” temperatures are obviously even colder than December.
Today’s 12z ensembles are locking in on the pattern than can deliver one shot after the other of arctic air in the 8-10 day range.
As for the snow, we still think we need to watch the models around the New Year for the threat of some southern stream energy interacting with the available cold air. That said, even without the southern stream, one must remain abreast of the challenge that a northwest flow pattern can produce.
Forecast models have a difficult time handling clipper systems in these type of patterns until within 24-48 hours within an event. Many times what appears to be a rather “harmless” clipper 4-7 days out can suddenly turn much more robust once the model catches onto the track and ability to literally squeeze out any and all available moisture from a cold air mass. Furthermore, the “normal” 10:1 snow ratio, many like to use, doesn’t apply in the least to these type systems. In cold environments you can easily get what’s called the “fluff effect” and snow ratios are more in the 20-30:1 range. Needless to say, it’s a challenging pattern that will keep us on our toes over the coming couple of weeks.
To summarize, we’re extremely confident on a colder than average close to December and open to January. We’ll have to monitor fast moving clipper systems that modeling will struggle with until right up to the event. Finally, we’ll keep a close eye on the potential interaction of the southern stream and cold air around the New Year time period for the possibility of a storm of “more significance.” Stay tuned!
Permanent link to this article: https://indywx.com/2013/12/23/impressive-cold-pattern-looming-beware-of-the-northwest-flow/
Sep 15
Rambling Around Between Games…
As we alluded to in the post earlier this morning, the weather pattern is beginning to get more active. As “seasoned” Hoosiers know, this is only the beginning of a rather “vamped up” weather period through the next 7-8 months around these parts. Yes, the lazy, hazy days of summer in the weather office are over. Speaking of the weather office, I’m continuing to get settled into the new “home base” office. As I get settled, more and more products will begin to hit the site to help keep central Indiana Hoosiers abreast of what lies ahead in the weather department.
As we look at the upcoming week, we’ll note the trough and dominant northwesterly flow of the weekend begins to “relax” by mid week and weak ridging takes it’s place. This will lead to a warmer and more muggy (though nothing close to as oppressive as last week) feel to the air by mid week. We also note another dip in the jet by next weekend. While details still have to be ironed out, there’s a good shot of rain due in here by week’s end along with another cool down by next weekend. I also want to point out the re-curving typhoon out in the western Pacific. This is in association with upper level ridge placement in the Pacific Ocean and we can actually use this tool to help us forecast weather here on the “home front” in the 6-10 day period. That would bring us roughly to 09.25.13 (give or take a couple of days) and would line up nicely with the cool end of the month we’ve been talking about for some time. Recall that we’ve said we anticipate a warmer than normal month to continue (in the overall pattern sense) up until the last 5-7 days of the month. Does this help set the stage for a colder than average October ahead? Stay tuned…
Here’s a look at our precipitation outlook, compiled this afternoon using a variety of short and mid range forecast models.
Watch how the troughs (cooler air) and ridging (warmer air) correlate with the temperature pattern in our official forecast (posted earlier this morning).
Monday
Wednesday
Friday
Saturday
Permanent link to this article: https://indywx.com/2013/09/15/rambling-around-between-games/
Sep 11
Wednesday Jet Stream Discussion
We use the Jet stream as one of many tools to help us forecast the weather in the days to come. A new feature here at IndyWx.com will be a Jet Stream Discussion, updated a few times every week to help you, the viewer, get a better idea of what to expect in the week ahead!
Note that the upcoming (7) day period will feature many “ups and downs” in the jet stream pattern. This is indicative of the changing of the seasons and very typical of the approaching fall season. Unseasonably cool air will be associated with the dip (known as a trough in the meteorological world) in the jet stream Thursday through Saturday. Temperatures will fall through the day tomorrow, after morning highs in the middle to upper 70s, and Friday and Saturday will feature air temperatures well below normal (by some 10 degrees). That said, the cool weather is “transient” and will be out of here almost as quick as it arrives. We’ll warm back to seasonable and above average levels during the early to middle part of next week as ridging builds into the Mid West and Ohio Valley region. In fact, temperatures well into the 80s to near 90 degrees can be expected by the middle/ latter part of next week.
As for precipitation, we anticipate a broken line of showers and embedded thunder to push into the region with the cold front later tonight and Thursday (not a big deal and most won’t get wet). On average, those that do see rain will only muster a couple tenths of an inch. The next best chance of precipitation isn’t until late next week.
We hope you enjoy these hand drawn maps. The way weather information is provided to you, the viewer, seems to become more and more digital with less of the “human influence.” Our goal, as always, here at IndyWx.com is to keep the human element in the forecast products you see here.
Our full forecast package will be updated later tonight. Have a nice and relaxing Wednesday evening and be sure to follow us on Twitter- @indywx or like us on Facebook (IndyWx.com).
Permanent link to this article: https://indywx.com/2013/09/11/wednesday-jet-stream-discussion/