We made it through one of the chilliest stretches to start May in a while. There were readings in the Great Lakes and Upper Midwest that suggested that numbers, like morning lows around freezing, or stretches below 50, had not been seen since about 2013. This time of year, that reads more as late winter than late spring.
Finally, though, 10, going on 11 days in, the persistent eastern trough is breaking down, and warm air is flowing back north through the Eastern US. And it will persist, with warm forecasts expected for most.
It has also been a dry start to May. April Showers may be through, but May showers are appreciated, too. The jet structure is going to be lifted along the Canadian border, and will be pocked with short undercutting waves. Bundles of energy to bring some precipitation into the picture as well.
You may note that this is not a uniform color scheme. There remains some below normal precipitation in the west, but the good news is, that this typically dodgy area is actually not in a drought this year. They will withstand some dry weather .
The rain is going to come in places where it is needed. The southeast and northwest remain thirsty, but the Plains are going to warm up, and be satiated for the next couple of weeks.
Our forecast this evening will take us to the South. It’s been cool this May. Does that apply to Alabama?
At 953PM, CT, Anniston was reporting fair skies with a temperature of 67 degrees. The area lay southeast of a cold front sliding listlessly through the Mississippi Valley, which accounted for a southerly flow in the region. The boundary will be reenergized by the daylight tomorrow. The boundary will arrive in Alabama tomorrow, with showers and thunderstorms likely. There is some disagreement on the timing for Anniston, but no doubt that the storm chances are high. The batch of energy will slow down, with clouds and rain hanging on through mid-morning, followed by a much cooler day on Thursday. Tomorrow – Afternoon rain and thunder High 81, Low 64 Thursday – Rain early, then clearing and colder High 73, Low 55
TWC: Tomorrow – Cloudy in the morning then strong thunderstorms developing later in the day. Damaging winds, large hail and possibly a tornado with some storms. High 77, Low 64 Thursday – Cloudy early with partial sunshine expected late. Cooler. High 72, Low 57
AW: Tomorrow – Mostly cloudy and humid; an afternoon thunderstorm High 75, Low 63 Thursday – A brief morning shower or two; otherwise, cloudy High 71, Low 56
NWS: Tomorrow – A slight chance of showers before 10am, then a slight chance of showers and thunderstorms between 10am and 1pm, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, High 82, Low 63 Thursday – Showers likely and possibly a thunderstorm before 1pm, then a chance of showers. Mostly cloudy, High 75, Low 59
WB: Tomorrow – Mostly cloudy. A slight chance of showers and thunderstorms in the morning then showers likely with a chance of thunderstorms in the afternoon. High 80, Low 69 Thursday – Showers likely with a chance of thunderstorms in the morning then partly sunny with a chance of showers in the afternoon. High 71, Low 56
WN: Tomorrow – Mostly cloudy with showers and a chance of storms High 82, Low 63 Thursday – Mostly cloudy with showers and a chance of storms High 75, Low 60
CLI: Tomorrow – Thunderstorm High 80, Low 63 Thursday – Light rain showers High 74, Low 55
There is an enhanced risk for severe storms in central Alabama tomorrow with this boundary. The front is pretty sloppy tonight, and things are clear in Anniston.
It’s not been common lately that I’ve been able to get the forecaster of the month post up early in the following month AND it is happening on a quiet weather day. Even more rare is that this month, every outlet had a share of at least one victory… except The Weather Channel. They remain in the lead for the year, but Clime had a very good finish to the month, and it brought them to victory.
I was more skeptical of the chances for rain in Logan earlier this week than most, because it looked like precipitation would be available for the higher terrain, and less so in the dry, urban locales of Utah. Not that I didn’t want it to rain, as this part of the world will take advantage of precipitation when they can. There was about a third of an inch on Monday, while Tuesday saw a few drips, but no actual reports of rain on Sunday. Clime had it’s second very good forecast verification in a row, earning the championship for the day. Actuals: Monday – .32″ of rain, High 51, Low 32 Tuesday – .01″ of rain reported, not measured. High 54, low 30
As we discussed, temperatures are staying cool for a lot of the eastern part of the country, and it seems as though we will be hunting warm air, if we can find it.
The CPC has issued their outlook, as of yesterday, for the 6-10 day, 8-14 day and 3-4 week outlooks. This is the 6-10 day outlook, but I assure you, the other two vary only slightly.
The jet flow is going to be bifurcated throughout the next couple weeks, with a strong jet running along the northern Gulf Coast. The Polar jet will be wavering along the Canadian border, often dipping into the US as a trough, ensuring some active weather, however the jet streak to the south will be an effective barrier to moisture rising into the continental US. We aren’t anticipating many soakers around the Great Lakes. This will do wonders for the drought in the southeast, though.
Even with successive waves from the northern jet, it’s really just seasonal thermal forcing that is going to break down the feature to the south and start allowing warmth and moisture back to the north. This isn’t expected to happen until around the 11th, though, which is why we have such a lengthy stretch of below normal temperatures East of the Rockies. It’s still nearly two weeks out, but the action of the northern jet by the 11th tells me that it won’t suddenly get hot in the northern tier, with ongoing showers and storms remaining likely, which will keep temperatures a little cooler if the showers are too widespread
If you are a fan of warm weather, this forecast is a bummer. If you are a storm chaser, this is also a bummer, as this should put a damper on what is historically one of the most active storm periods on the calendar. If you live on the West Coast, you can ignore everything above and enjoy the beach.
Our forecast for Brownsville was for hot, humid days over the weekend, which was expected to lead to some morning fog, especially on the coast. Brownsville is further inland, but even there, the atmospheric moisture was so thick that the condensate was registered as .01″ of precipitation on Saturday. It was still plenty hot and plenty humid in the afternoon when the fog was burned off. There was a three way tie among our most unexpected trio: WeatherNation, WeatherBug and Clime. Actuals: Saturday: .01″ of precipitation, High 88, Low 75 Sunday – High 90, Low 78
Just after sunrise on April 27th, the SPC elevated the thunderstorm forecast for southeastern Missouri to a moderate risk. A deep upper level trough was generating a strong area of low pressure in the Plains that was feasting on the chaos of colliding air masses. Cold and Canadian with tropical and maritime. The helicity in the atmosphere meant tornadoes were likely.
There were indeed several tornadoes from Missouri to Indiana, with a great deal of damage wrought by straight line winds. The tornadoes were embedded within a line, and at some point, it becomes a bit academic as to whether damage is caused by winds or tornadoes.
The changes to the SPC and the deeper set of information within the convective outlook are new features to the thunderstorm season. I wanted to take this specific example to look at what the SPC released, and see what factors best correlate to the outlook that is provided. First, here is the outlook, issued in the early hours on Monday.
As a bit of background, the change that was recently made to the storm hazard maps added a storm intensity rubric to go along with the probability guidelines that had been a part of those maps before. Take a look at the wind and hail maps to get the idea.
So, you can see there was a high probability of strong wind, and a lower probability of hail, but the hail in the forecast was expected to be larger. We can also see that neither the high probability of severe wind, or the expectation of large hail defined the moderate outlook boundaries. That’s not particularly surprising. That the significant hail in central Texas didn’t lead to a higher outlook than a marginal risk in central Texas surprised me, though.
Moderate and high risk events generally need a threat of tornadoes, so let’s look at the tornado outlook issued at the same time as the full outlook.
The threat for strong tornadoes is only designated on the charts as 1, 2 or 3, and the probability of a tornado within 25 miles of a spot is more well defined. Perhaps it is no surprise, then, that the moderate hugs the 15% chance of a tornado risk. I’m sure it didn’t hurt the case that the forecast was a level 2 on the intensity scale, either.
For what it’s worth, here is the break down of severe reports.
This is a cool trip, with a route through the mountains. lasting three days and covering 1,671 miles. That breaks down to about 66.8mph, and two days of 534.7 miles, with a longer day at the end. It’s going to be pretty scenic, I think!
DAY ONE (Monday)
Brownsville, Texas
As you may have heard, there is severe weather in the Plains tonight. It will be more widespread and significant tomorrow as the low shifts to the Mississippi Valley. A cold front is expected to dangle off the southwestern flank of the feature, with strong thunderstorms possible. There is significant disagreement in the models as to whether storms will fire along this front as far west as our route, but if they do intercept, it will be around Eden, Texas. We won’t escape the state by the end of the day, rounding out the day in Forsan, near Big Springs.
DAY TWO (Tuesday) The drive on Tuesday will be through the back roads of west Texas and New Mexico, including a pretty good cross section of Albuquerque. The big area of low pressure will be transitioning well away from the middle of the country by midweek, so the drive will ultimately be partly cloudy, with a bunch of scenery to enjoy. We’ll reach Counselor, New Mexico, halfway to Farmington.
DAY THREE (Wednesday) Soak this day in. We’re going to trek through some of the most beautiful country the nation has to offer. We’ll run past several national parks, Moab and other tracts that aren’t federally protected, but still attractive. The weather will cooperate, with overcast coming back into the picture between Salt Lake and Logan. It will be one of the more exemplary drives we’ve taken, and the weather will generally be pretty great, too.
We are headed to the Utah Panhandle for our forecast today. Have you ever been?
At 151PM, MT, Logan was reporting light rain, and a temperature of 43 degrees. A deep trough aloft has helped generate a strong area of cyclonic flow centered over northern New Mexico. Scattered showers are widespread across the Central Rockies, with snow common at elevation. Logan is on the back side of the feature, and is enduring the cooler wet weather. Despite the surface feature intensifying and shifting towards the Great Lakes, moisture will remain strewn through the Rockies, riding the northern flank of the jet. Spots of rain will be in the forecast through the day tomorrow but ultimately, the vigorous jet is the culprit, and will carry most of the moisture at altitude. Rain and snow will thin vertically, and Tuesday morning will be dry in Logan, but not in the Wasatch. Tomorrow – Mostly cloudy, scattered showers, High 51, Low 35 Tuesday – Partly cloudy, clearing, High 56, Low 32
TWC: Tomorrow – Overcast. High 52, Low 33 Tuesday – Intervals of clouds and sunshine in the morning with more clouds for later in the day High 55, Low 31
AW: Tomorrow – Cool with intervals of clouds and sun; widely separated afternoon thundershowers High 52, Low 33 Tuesday -A shower in the area in the morning; otherwise, mostly cloudy High 55, Low 34
NWS: Tomorrow -Rain showers likely before 9am, then rain and snow showers likely between 9am and noon, then rain showers likely after noon. Some thunder is also possible. Mostly cloudy, High 52, Low33 Tuesday – A chance of showers, with thunderstorms also possible after noon. Partly sunny High 56, Low 32
WB: Tomorrow -Snow showers in the morning then snow showers rain showers and a slight chance of thunderstorms in the afternoon. Mostly cloudy. Accumulation 1 inch High 43, Low 33 Tuesday -A chance of snow showers and a slight chance of thunderstorms in the morning then a chance of snow showers rain showers and a slight chance of thunderstorms in the afternoon High 47, Low 33
WN: Tomorrow – Mostly cloudy with a light wintry mix and isolated storms. High 52, Low 33 Tuesday – Partly cloudy with scattered showers and isolated storms, High 56, Low 32
CLI: Tomorrow – Heavy snow showers High 50, Low 32 Tuesday – Light rain showers High 53, Low 31
There is some variability on the end time for precipitation. I feel as though the position at the var northern end of Utah will isolate Logan a bit from the steering flow and dry them out a bit. Only one way to find out. It is quite wet tonight, however.
