MCS...YES

It always feels nice when the SPC changes their forecast to your own forecast....and that is what happened last night. I am sure the SPC knew the possibility of an MCS was there, but they didn't want to go out on a limb and forecast a slight risk for a certain location (which would likely have been further south 3 days out) when the actual location of the event might have been somewhere else. At this point though, everything seems to be in line for a decent MCS moving through the central plains Wednesday evening and night. High wind gusts and large hail will be the primary threats from this system, with an isolated tornado threat possible in the Northern High Plains in the late afternoon and evening from western Nebraska to the western Dakotas.

I didn't really get into the threat of severe weather in the northeast last night, and I guess I should have considering the storms that have developed up in that region today. Decent lapse rates and dewpoints in combination with a substantial upper level low are resulting in the storms today. The SPC has also outlooked this area for storms tomorrow, but I really haven't looked that much into it. Lets be honest, I live in the Plains, so this blog will center on the Plains.

MCS development will be likely Wednesday into the weekend. It is possible Thursday is a 'slow' severe weather day without a strong MCS but the MCS train will likely start up once again on Friday. Reminder: Once one Derecho or strong MCS develops in a certain environment it is very likely for a second one to develop the next day (or sooner) should the environment not change. In this case, the first Wednesday night event will be associated with a shortwave moving through the region...Thursday will lack this same substantial shortwave. But moisture will increase into the weekend, so the severe weather threat will likely once again increase.

Now it is time to go golfing and then come home and work on my thesis some more. I am getting there and have 5 days to get it done. I was invited to go bowling tonight...but I think working on my thesis would be the better, more responsible thing to do considering the time crunch!

MCS in the Making?

Tomorrow doesn't look all that impressive on the severe weather front...tropical front...except maybe on the front through Florida. However, not impressive in a severe weather sense, but more the fact that Florida is going to see A LOT of rain over the next 4 days. A front is stalling out over the center of the state and I wouldn't be surprise, considering the tropical wave which is moving into the gulf, to see areas with 6+ inch totals over the next few days. But we shall wait and see.

Anywho, this entry is really about the chances for a nocturnal MCS with the threat of wind across the central plains. The models have sure trended down with the threat over the last 24 hours, now with the NAM moving the system a little north through Nebraska and maybe northern Kansas, and not bombing it out like it did yesterday. The GFS and NAM are now very consistent with the placement of the system and strength, which gives me a bit more confidence.

Currently both models are indicating a surface low developing in western Kansas leading to southerly flow into the Central Plains. This southerly flow will increase dewpoints across northern Kansas and Nebraska back up into the middle 60s (a little higher than the 52 dewpoint we experienced today in Wichita!). At 500 mb the flow will be out of the northwest (thus called Northwest Flow....) with a shortwave moving into the central plains Wednesday afternoon. This shortwave and increasing low level jet into the evening will lead to thunderstorm development across western Nebraska along the warm front. The low level jet will be nearly due south in the early evening as the MCS begins to evolve in Nebraska but will turn out of the southwest as the system moves towards the east into the Omaha and Kansas City areas. This will allow the MCS to continue its eastward propegation...and if the system can stay surface based, could have some decent wind threat late into the night and early morning.

Currently the SPC has a 5% chance of thunderstorms for this area....which makes me wonder if I am just crazy. But the conditions look decent for a good thunderstorm complex to develop and treck across the plains...so I am not going to back down...yet. I will be very interested in seeing the day 2 forecast that is issued later tonight.

ADDITION:

And here is the outlook for Day 2 (Wednesday):

A Relative Calm

The next couple of days can be expected to be relatively calm compared to the storms which impacted the country from the Dakotas to the Gulf Coast the last three days. Storms will continue in Florida through Texas and up the High Plains with strong wind gusts and large hail the threats. No real high risk of a major wind event or tornado threat is expected. However, models seem to be trending towards the risk of a large MCS on day 3...or Wednesday. Both the GFS and NAM develop this system, with the NAM being much stronger than the GFS. It will be something to watch and I will go into more detail tomorrow night if the models are still showing it. Currently the NAM has a shortwave at 500 mb traversing from the High Plains through Kansas Wednesday night in northwest flow. Dewpoints should be back into the mid 60s to lower 70s with highs in the mid 90s across much of Kansas.

Thesis Writing and Hot Weather

I haven't been updating this for a long time, but I thought I might as well start it up again. This first update will be brief and I will start getting into more of a weather blog once again next time (hopefully tomorrow after work).

I have been working on re-writing my thesis now for a month and a half...and I tell you, it is not easy. The reviewers have asked for many small...and large...changes to the manuscript and it takes a lot of time. But I am getting there. I hope to be close to done by the 3rd or 4th of July and maybe, just maybe, you will get to read my thesis in Weather and Forecasting.

As for the recent weather, there is only one word that describes it: HOT! We went golfing a few days ago at 2:15 in the afternoon on a day when the high was 98F and the dewpoint was in the lower 70s. And we played as a group of 5.....not smart. The large group resulted in us taking 3 hours to play 9 holes! In 100 degree heat index weather. Definitely not the smartest thing I have done. But I shall learn from that mistake and play in the late afternoons on these really hot days in the future.

The storm chasing year has been nice to me. Saw two tornadoes...and could easily have seen 6 more if Shaina and I didn't decide to call off the chase one day and go to a nature preserve. But that's how it goes. There will be more opportunities next year.

I will update either later tonight before I go to bed with a weather discussion or tomorrow evening. As for now, back to editing the thesis.

Severe and Snow

It looks like there really isn't too much to add from my last blog post. The snow threat has increased substantially with all of the thickness values now turning over to all snow. The soundings in South Dakota look very promising for snow as well, along with momentum transfer of up to 60 knots of winds! What does this mean? Blizzard conditions can be expected from Rapid City to Mitchell, SD and north. I wouldn't be surprised to see snowfall totals in the 6-10 inch range in much of central S/N Dakota.

The severe threat is still considerable, however the moisture return actually does not look like it will be has high as I expected. The tornado threat is still there, and we could see a few isolated tornadoes in the central northern Oklahoma to southeastern Nebraska region as the storms fire in the afternoon on Wednesday. Quickly, however, a strong squall line will develop resulting in a much greater wind threat. I wouldn't be surprised to see a vast area of 70 mph wind gusts as the line tracks through eastern Kansas/Oklahoma/Nebraska into Missouri/Iowa/Arkansas.

This is going to be a major fall storm. The strongest of the season so far. If you are in the Dakotas, make sure to keep indoors. If you are in the area with a severe threat, make sure to keep that weather radio on in the event severe weather threatens your area.

Severe Threat Wed-Thurs

A severe weather threat will materialize this coming Wednesday evening into Thursday as a strong storm system pulls out into the plains. Currently this system hasn't even interacted with the United States yet, but will pull on shore of the California coast tomorrow. The strong 500 mb trough will begin to dig into the plains early Wednesday, becoming slightly negatively tilted and bringing along a substantial amount of vorticity. The low will close off over Nebraska Wednesday afternoon and evening, deepening the low and enhancing the dynamics of the system.

Moisture return seems like it will easily be set up for a severe weather event with dewpoints already in the 50s in Wichita, KS. This will only increase as we go towards Wednesday, likely reaching into the 60s. Storm relative helicity values near 400 are predicted by the NAM Wednesday afternoon, resulting in high EHI values. The threat for supercells at initiation from northern Oklahoma into Iowa seems possible, with the greatest threat from central Oklahoma into eastern Kansas. The NAM and GFS initialize convection in the Wichita area. Could get interesting.

Quickly the strong dynamics of the system will take over, likely resulting in a substantial squall line / high wind event. However, as the storms initialize a tornado threat will be very much possible. The tornado threat could stretch from Iowa to Oklahoma before the line goes linear and moves to the east into Thursday. 850 mb winds in Kansas look to be 50 knots as the cold front and dry line approach. The triple point might move right through the Wichita area.

Out ahead of the storm on Tuesday will be a substantial synoptic wind event, with 55 mph wind gusts possible along the entire front range and much of New Mexico. Additionally, some wind gusts to 50 might occur in northern Arizona. Wind gusts to 45-50 mph could occur even in the Wichita area before storms develop on Wednesday.

A decent blast of cold air will move into the northern plains behind the storm, possibly leading to a snow event in the Dakotas. The central Dakotas look like to be the area of greatest threat currently, but knowing the last system and how it didn't quite get cold enough with much the same set up as this one...it will be close. However, the threat is there. Strong winds will also accompany any snow or rain on the backside, possibly leading to blizzard conditions if the precipitation is snow.

Also, watch out along the eastern coast as the models are now unanimously producing a substantial hybrid system that moves along the Atlantic seaboard bringing not only the threat of some heavy rainfall, but gusty conditions along the coast. The rip tide threat will be high.

Negative AO = Cold Weather

Now, I know I keep going over this, but just look at the 00Z GFS model and you will see it happening. The GFS has been keeping it warm for so long now, building that ridge in the center of the United States. Now, here is what it looks like at 500mb:

Thats 360 hours out, yes I know...its unreliable. But even go back to 240 hours out and you can see the cold shot developing. The negative AO is starting to pan out, the cold weather is on its way. A cold and snowy eastern United States is starting to look more and more likely for mid-November and on. I forecasted snow for Anderson, Indiana on November 14th. I will stick to that forecast. And I will also stick with snow in Wichita, KS on November 21st. It might be a white Thanksgiving for much of the country, just as Joe Bastardi keeps predicting.

PS: The storm for next week, from the Tues-Thurs period, is still looking like a large scale severe weather event. Of course, mesoscale features will be very important to the event, and we will have to wait and see how the thermodynamics pan out. However, right now the trough digs deep into the plains, produces the bowling-ball of positive vorticity, plowing into the panhandles of TX/OK into Kansas, and quickly becomes negatively tilted. The makings for a severe weather event, and then possible backside snow storm are there on the synoptic scale, there is no doubt about it at this point. Of course, as we know, models can change...so we will have to keep a close eye on this.