Category: Monthly Outlook

Updated 04.01.21 @ 7:43a

While April is getting off to an unusually cold start for a good chunk of the country, this (thankfully, for most) won’t be the theme for the month, as a whole. We anticipate a quick bounce back in the temperature department over Easter weekend and on into next week. We’ll let our shorter term products handle that and focus more on the month, overall, with this post.

Let’s take a look at some of the various modeling for the month of April.

JMA take-away: large scale drier than normal conditions with widespread warmth (exception being the immediate West Coast and Southeast).

CFSv2 take-away: widespread warmth through the central and north along with widespread drier than normal conditions (exception being the northern Rockies/ western Plains).

European Weeklies take-away: large scale drier than normal with warmth through the central, upper Midwest, and Northeast.

From a teleconnection perspective, you know we really like to key in on the NAO this time of year. Should that flip negative, then blocking would likely force a colder pattern into our immediate part of the country (can also lead to wet times, as well). That doesn’t appear to be the case this year- at least over the next few weeks. Perhaps what’s more interesting is the MJO as it’s showing signs of wanting to be more amplified throughout the coming weeks.

You get a transitional theme in the temperature department as the MJO traverses phases 4-7 this time of year:

The one constant (exception being Phase 7) is relative warmth throughout the Plains.

Given all of the above, we’re leaning towards a widespread warmer than normal month and relatively quiet month, as well, given the time of year.

Updated 01.31.21 @ 9:35p

As we head into the last month of meteorological winter, there are growing signs we’ll have to contend with some of the most significant cold so far this season. Add in the fact that the pattern drivers are more aligned to continue the recent active times and things could get quite interesting in the weeks ahead.

For the first time this winter, it appears as if the teleconnections will combine to favor not only a continuation of the active storm track, but also argue for the likelihood of more sustained cold air (especially compared to Dec. and Jan.).

Note how the latest CFSv2 monthly product continues to shift colder for February.

We believe the AO, NAO, PNA, and EPO will remain negative through the majority of the month. Getting the EPO negative would be a big deal and go a long way in supporting the idea cold would be able to stick around with more staying power relative to normal. (The threat of significant arctic air getting into the mix during the 1st half of the month is a growing concern). The negative PNA would favor southern ridging and help to direct storms further north than what we would see otherwise- especially given the strongly negative AO and corresponding blocking.

Note the how the European ensemble shows the colder anomalies overspreading the country through the first couple weeks of February.

Given what we’ve discussed above including the MJO movement, this has merit.

The busy pattern will produce frequent storm systems through our general neck of the woods and with the more widespread cold around, I think we’re looking at multiple winter weather threats of significance through the month. Needless to say, I believe the month should produce above normal snowfall (average at IND is 6.5″ for Feb.).

Here’s our monthly outlook, including temperatures that should average 1° to 3° below normal with 1″ to 2″ above normal precipitation in Indianapolis, itself.

Winter weather enthusiast? Giddy up!

The way modeling has been “forced” to correct colder over the past week to 10 days to open December has been staggering. Without question, the initial driver of this change has to do with the strongly positive PNA. Note how this is forecast to remain strongly positive over the upcoming week before trending neutral by mid-month.

This favors a trough over our part of the country and into the Deep South through the better part of the upcoming couple of weeks. We’ve been posting about how the strongly positive PNA could lead to other teleconnections aligning in a manner that could lead to the possibility of more “meaningful” or longer lasting cold beyond mid-month. The trends of the AO, EPO, and NAO have been towards this colder direction over the past few days and it’ll be interesting to see if these trends continue.

Perhaps more importantly has to do with the MJO. While the majority of guidance keeps the MJO in the “null” phase (meaning we’ll lean heavier into the teleconnections above) into and through mid-month, it’ll be worth keeping a close eye on this. The one outlier is the Canadian taking a highly amplified MJO towards the cold phases (after blasting through the warm phases quickly) by mid-month. Again, we’re not throwing our eggs into the MJO basket right now and prefer to lean heavier on the tele. trends.

The latest CFSv2 has been trending colder for December with each model update- especially over the Southeast and TN Valley:

The latest European Weeklies are somewhat similar, but colder across the West.

The JMA Weeklies want to put the ‘mean’ trough (and associated cooler pattern) over the Southeast for December:

Consensus of longer range, monthly products places an area of widespread drier than normal weather across a good chunk of the country:

While there are obvious reasons for a lower confidence forecast around mid-month, thinking here is that we’ll maintain a seasonal to slightly colder than normal regime for our immediate region into the Southeast this month. This is quite different than the recent December torches we’ve been dealt and may seem much cooler than normal as a result. I believe the strongly positive PNA will “force” those other pattern drivers towards a manner that will drive the cooler pattern for the better part of the month before potentially trending milder around Christmas and New Years.

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