June forecaster of the Month

We are now halfway through the year, and have now clearly defined a best forecaster so far this year. After a three way tie through May, Weatherbug had the best month in June, and Victoria-Weather and The Weather Channel did not, giving them the lead as we head into the dog days of summer. Hurricane season and record breaking heat are around the corner, and meteorologists are surely around the corner, so continued forecast vigilance will be necessary.

OutletForecast Wins
The Weather Channel4.83
National Weather Service2.16

Pacific Northwest is baking

The pattern across the country has once again stalled, and it is going to have dangerous effects in the Pacific Northwest. A severely tilted trough is holding up traffic across the country. A weakening system in the middle of the country is being propped up by a severely tilted trough, which in turn is blocking a ridge wrapping in from the west.

The strength of the ridge, and the continued entrenchment of the ridge are pushing temperatures to record totals. Not just for the day, or the month, but all time. Check out some of the totals from the Portland weather service office so far.

The trough is continuing to weaken in the middle of the country, which should allow the ridge out west to break down and start propagating to the east. Temperatures in Portland, which are, at the moment, sitting at 111, will start dropping after Monday, which will again hit well into the triple digits.

The summer, in particular the next few weeks, look like they will be above normal, however fortunately, the record breaking heat looks to be near it’s end. Without this particular wave to focus on, the attention will be turned to the persistent drought still smothering the west coast, and is being worsened in parts of the Pacific Northwest, no thanks to the inferno.

Ground truth

I am presently enjoying a vacation with my extended family in the Black Hills of western South Dakota, and we’ve had a bit of active weather in the last couple of nights. Tonight, we were in a severe thunderstorm watch, as a line of thunderstorms swept in from Wyoming and brought rain and marble sized hail to our cabin before getting a boost from the eastern slope of the Black Hills, and accelerated through Rapid City and is now preparing for a voyage through the Plains.

Last night, however, was different. An isolated thunderstorm, aided in part by the very mountain we are staying on, cropped up and stayed in the same spot for well over an hour. Here is the view from just to the north of the storm.

We were almost directly under this storm, and the radar confirmed our suspicions.

The storm did eventually expand and bring some drops of rain, but not as much as points on other faces of the mountain!

It was an interesting thing to see in action, the force of the terrain, and the structure of the storm that produced all of the wet weather to other parts of the mountain was pretty incredible.

The temperature map gets flipped

It was 90 degrees in Minneapolis today, which is certainly a pretty warm start to June, and tomorrow and the weekend will only get hotter. Heat waves are certainly newsmakers, and in particular, they are big news when they arrive in the northern US. All this is true, and really, it’s not the most interesting part of this particular heat wave. Take a look at the forecast highs for Friday.

There is the typical hot spot in the Mojave, but otherwise, the warmest part of the country will be…. North Dakota? The interesting part of this heat wave, to me, is that it completely bypasses places to the south. The forecast high in Bismarck tomorrow is 101! Unintuitively, the forecast high in Austin tomorrow is 80, a full 20 degrees cooler. I don’t have to tell you this, but that’s not how it usually works!

Why is this going on? The answer is told in the upper air forecast. Take a look at the flow pattern forecast during the day tomorrow. I have added some arrows for your benefit.

The pattern over the US is tilted. The upper level trough over the eastern part of the US takes a westward turn and heads through the southern Plains. Forgive me, because the axis of the trough in the south is a little further north than I drew it, but the result is the same. Moisture is being drawn to the Red River Valley, and then it streams into the eastern Great Lakes, keeping the entire tract covered in clouds and rain.

Meanwhile, a ridge axis runs from the southwest towards the Upper Mississippi Valley. Remember how I noted how hot it was in the southwest? Well, that is where the air moving into the Dakotas is coming from. Combined with the scouring effect of the Rockies, the dry air can warm even more during full daylight.

When this pattern sorts itself out, the hot air won’t go anywhere, but instead of shipping off to the northeast, the moisture entering through Texas will find a route north. Until a cold front comes late next week, the heat of this weekend will become hot and humid.

It’s only June 3rd. and the summer is off to a hot, hot start in the Northern Plains.

May Forecaster of the Month

We made it through what is historically the stormiest month of the year, and made it without many devastating headlines. Now we just need to tackle fire and hurricane season with so little bad news. This month, the best news for a forecaster belongs to The Weather Channel, who always seem to do well in the spring storm season. Kudos to them. Here is the look at the total wins for the year to date:

OutletForecast Wins
The Weather Channel4.5
National Weather Service1.83

Tornadoes in Chase Country

There has bee quite a bit of severe weather in the last week, but it hasn’t really been a story in the news. Strong storms did a good job of avoiding large population centers, and never really threatened to move somewhere moer ominous. Any weather outbreak looks as though it will have to come at another time, as the severe weather in the Plains is going to wear itself out.

Tornadoes are common this time of year, and in the High Plains, thanks to the changing of the season, and the topographic advantages of the region. The flat, generally low density population of the region makes it popular with storm chasers, both of the academic, researching variety, and the thrill seeking tourist kind. The availability of weather data to the public has meant that May in the Plains can be thick with chasers, especially when the weather is busy. Such was the case over the last week, when tornadic activity was seen over many days from the Texas Panhandle to southwestern Nebraska.

Many videos were taken and twisters spotted, all without much harm to life or property. Call it a pretty successful chase season for all involved (except those who justifiably are a bit miffed by the idea of disaster tourism, especially in their home area).

The region, as I said, is a topographically perfect partner for storm chasing. The pattern this week set itself up nicely, and was long lived enough to encourage chasers to make the trek. There weren’t big areas of low pressure that dived into the region to make for dangerous outbreaks, like we see in the southeast or Ohio Valley when outbreaks occur there.

The Omega block over the eastern US allowed for warm, moist air to pump north on the western flank of the ridge, priming the pump for strong storms. In this environment, the tightly spinning lee troughs developing in the leeward side of the Rocky Mountains were able to trigger thunderstorms that were often well organized enough to drop tornadoes, often big, nasty photogenic ones that could be filmed from a distance.

In this case, they didn’t find any population centers, which is what everyone wants. With any luck, important information was collected. At the very least, cool images were taken.

An Omega Block takes up residence in the US

In the past several years, some long standing meteorological terms have filtered out into the masses, and have exploded as buzz phrases, and often help to drive ratings and induce a mild hysteria. Think of how often you now hear the terms “polar vortex” or “bomb cyclone” for example. Right now, many meteorologists are talking about an “Omega block,” which is definitely much more innocuous than it sounds.

For those that are familiar with the Greek alphabet, you may know that the letter Omega is the last letter. This lends the Omega block terminology a bit of gravitas. Is it some sort of apocalyptical signal? Is it the end? No, assuredly not. The name is actually a reference to the shape of the Omega: Ω. The upper level jet features a ridge, bracketed by two sharp, potentially cut off areas of low pressure. This is the case today, and will be for a while.

Ridges in general are tough to dislodge, and having a immobile trough, as is the case off shore, in front of it, and even undercutting it, slows things down even more. This is why it is called a “block”. For a while, the upper level pattern is going to be unable to progress.

There isn’t a lot of danger in the pattern, especially at it’s current location. A little further east or west, the coasts could be in for a fairly rainy week, or the Plains could be in line for a major severe weather stretch, with low pressure unable to move our of the region. Instead, it will be dry from the Mississippi Valley to the East Coast, with just a few showers riding the western side of the ridge, a persistent but not terribly worrisome threat (despite a few tornadoes dipping down over southern Minnesota earlier in the week. )

This Omega will be in place through the weekend before it slowly starts to shuffle off to the Atlantic.

Guidance agrees on one thing: Action

Tuscaloosa Tornado, 2011

Today is the 10th anniversary of a major tornado outbreak, which caused death and destruction across the southeast, most notably when a tornado hit Tuscaloosa, including the campus of the University of Alabama. This time of year has no shortage of such anniversaries.

This year, fortunately, there aren’t any major severe weather outbreaks on the immediate horizon. Model guidance is in lockstep over the next few days, so that can be taken with some degree of certainty that there isn’t a major event before the end of April.

That’s not to say it won’t be stormy. Every increment of the forecast features a little wave, producing showers and thunderstorms rolling through the country, particularly from the Central Plains to the Ohio Valley southward. It’s not always the same wave, and no area is going to be relentlessly active for the next several days, but there will certainly be many active radars in the south central and southeastern US through the end of the work week.

Beyond nationally calm Saturday, divergence begins to settle in. Timing and placement are askew for the various computer guidance that meteorologists have available. Going beyond 5 days for a forecast is never generally as accurate as one might hope, but for a lot of the country, Sunday and the early part of next week are all over the map.

One thing that is in concert, is that none of the model maps are quiet. There is always something going on. A broad trend like that can be relied upon, moreso than a forecast for a particular location. That means the country can expect to see a lot going on in early May, even if we can’t confidently say what we should expect quite yet. With the anniversaries of Tuscaloosa, Moore and so many other coming up this time of year, “action” is not something everyone should look forward to.

Average hurricane season now a little busier

Every ten years, weather averages are reconsidered and updated. Daily high temperatures, low temperatures and precipitation are now based on the most recent 30 years, reflecting the most recent information in our ever changing climate. In addition to the daily changes, monthly and seasonal changes are also instituted.

Hurricane seasonal averages were updated, replacing the 80s with the extremely active 2010s. Now, an average season will see 14 named storms, with 7 hurricanes, up 2 and 1 from the previous averages, according to the National Oceanic and Atmospheric Administration. This is has a lot to do with the active years early in the past decade, and especially the last several years, which were busier than even the new normal years.

There is something to be said about the warming of the north Atlantic, but also, the El Nino pattern, which was more prevalent in recent years. Somewhat surprisingly, the eastern and central Pacific didn’t have any revision to their annual averages. The Atlantic also didn’t see an increase to the major hurricane forecast.

Satellite data and naming conventions really were revolutionized in the 90s. Improved satellite data will, as a result, not be a factor in future changes to averages, but they may have led to some change in this update. Hurricane season, officially, begins on June 1st, and we are coming off the busiest season of all time.