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Western and Northern Virginia

Entries in this blog

 

Significant Storm for Tuesday into Wednesday

For far western areas along I-81 between I-64 and OKV An area of low pressure will move out of the northern Gulf of Mexico and up the east coast tomorrow and Wednesday. As it does, light precipitation will begin to overspread the area early tomorrow morning and will increase in intensity throughout the day … before beginning to taper during the overnight and possibly end as a period of snow Wednesday. Initially, there will be just enough cold air in place for some spotty flurries during the p

thunderman

thunderman

 

Rapid Clearing Expected This Evening

I have been really slacking as of late on the blogging ... hoping to fix that! Mediocre line of storms developed over the central Shenandoah Valley this afternoon and prompted a local blue box from Sterling around Charlottesville. There was a single report of wind damage in the city limits as well ... so congrats Sterling on the verification. Another line of storms lies further west from west-central Illinois through IND and down into LEX/central Kentucky ... high level blow off from this act

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thunderman

 

Flash Flood and Possible Isolated Tornado Threat Thursday - Saturday

An area of low pressure is expected to come out of the Gulf of Mexico and up the east coast, while another disturbance approaches us from the West in the Thursday - Saturday time frame. These two systems will attempt to pump in a rich plume of moisture from the south and east, setting the stage for heavy downpours with any showers and thunderstorms that develop. No widespread severe weather is expected, but I would not rule out an isolated tornado with this system(s) ... with a somewhat favorabl

thunderman

thunderman

 

May 31, 2013 Oklahoma City Traffic/Chaser Debacle

I generally stay away from opinion posts in this blog, but the events that transpired yesterday deserve attention. First, I think that it needs to be pointed out that chasers and spotters provide invaluable information to the National Weather Service in the form of ground truth. This is a concept that most of the general public (and even some meteorologists) on the East Coast do not fully understand. Without these folks burning their personal gas, warning lead times could be substantially dif

thunderman

thunderman

 

Virtual Storm Chase

There is a great competition called Virtual Storm Chase that has been given new life (for bragging rights only). This is the same competition that was started over on the old wxchat forums several years ago (mid 2000s). For those that do not know what it is, I have a attached a PDF copy of the rules below. It is a great learning experience for those interested in severe weather forecasting and a great way for even meteorologists to keep sharp. http://virtualstormchase.info The site "appears

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thunderman

 

Update On Severe Weather Threat Next Week

Not much has changed. It is starting to look as if the warm sector will continue East in active form. Could see a multi day severe weather outbreak from the Plains to the Ohio Valley/dixie alley. People in KS, OK, MO, and AR really need to be paying attention to this. Original blog post on this: http://www.americanwx.com/bb/index.php/blog/8/entry-95-early-week-plains-severe-threat/

thunderman

thunderman

 

Early Week Plains Severe Threat

Looks to be a significant severe weather threat early next week. An area of low pressure is expected to develop and move off the Rockies … as usual with upper level energy approaching/crossing the Rockies. Ahead of this system, there will be an extended period of northward return flow off the Gulf of Mexico … setting the stage for a moist and unstable boundary layer as our system moves in around Monday. A dry line will develop across Western parts of Kansas, Oklahoma, and Texas. As the dryline

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thunderman

 

Light to Moderate Snow to Continue Through Into At Least Early Evening Hourse

Light ... to at times moderate ... snow will continue into the evening hours, as the upper level low moves slowly Eastward. Despite the snow, accumulations have been tough to come by thanks to a combination of above freezing temperatures and the late March sun angle. However, as we move closer to sunset, the snow will accumulate easier (much like we saw yesterday evening) and we could see up to another inch I think in some places. Some slick spots could develop as well later this evening on road

thunderman

thunderman

 

Palm Sunday - Monday (3/24-25/13) Threat

While still being a day 5ish event, it is not to early to start looking at some of the possible implications of various models. At this juncture, we generally have the GFS and the Euro book-ending a possibilities window that includes a cutter to Chicago and a more suppressed system that goes East of Hatteras For the most part been consistently left of the GFS ... with its ensembles a tad to the right of the operational Euro (but no where near the GFS). The 12z GFS Ensembles cut the difference

thunderman

thunderman

 

From: 1/21/13 Dixie Alley Severe Threat

The area of low pressure that we are all watching for winter weather possibilities next towards next weekend, looks as if it may have quite the significant severe weather side as well on Thursday. The area of interest will be from east Texas into Dixie Alley. As we saw with the last event on Sunday, there looks to be a small area of sufficient moisture return along and ahead of the front across LA, MS, AL, southern AR, and east TX. This area of better moisture/theta-e looks to also be co-locate

thunderman

thunderman

 

Winter Weather Potential Thursday Night/Friday

As I am sure most are aware, it looks like we will have significant to major nor'eater on our hands for the Thursday-Saturday time frame. While our friends up north look to clobbered, we will unfortunately be getting screwed. The main issue with this event for our area is going to be temps. High pressure to the north will keep cold air in place for the beginning of the event (Thurs night) ... with temps likely ranging from the upper 20s/around 30 (West of Blue Ridge) to lower/mid 30s (Leesburg,

thunderman

thunderman

 

Dixie Alley

First of all, I do not intend this blog to be a severe weather blog, but the weather around here lately has been boring. The term "Dixie Alley" gets tossed around a lot this time of year and it is never really defined beyond that. For those that aren't aware/aren't severe weather junkies, I just to briefly define it. "Dixie Alley" is essentially just a an extension of the traditional tornado alley into the Southeast and lower MS River Valley. In the late Winter and early Spring, the dynamics of

thunderman

thunderman

 

Possible Plains & MS River Severe Weather Episode Next Weekend

Some type of severe weather threat is appearing more likely around the Saturday time fame from KS down into northern TX as a low develops on the flat side of the Rockies and works to setup/organize a dry line and triple point region. As the system pushes east, there is the potential to have a respectable cold front kicking into a moderately to highly sheared 60F+ Td warm sector along the MS River/Dixie Alley. Obviously too early to start boarding the train, but there is def potential for this

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thunderman

 

Evening/Overnight Tornado Threat in MS River Valley Region

Eventual tornado threat will depend on how unified the current line of storms becomes. If it can manage to maintain some semi-discrete updrafts within the line, then all current data points towards a significant nighttime outbreak across AL/northern LA/western MS. The combination of boundary parallel upper SR winds and low level SR winds on the order of 20-40 knts has me personally a little worried about a too unified squall line ATTM for a significant tornado threat. Some guidance manages to k

thunderman

thunderman

 

MS Valley Severe Weather Outbreak Potential 1/28/13

Severe weather outbreak looking more and more possible across portions of the lower Mississippi Valley and deep south tomorrow and tomorrow night. This evening the culprit low is located across western Kansas with a warm front stretching along the Kansas border and into northern Missouri. The dryline is located from west of KICT down through western Oklahoma and Texas … roughly along a line from Altus, OK to Sweetwater, Texas and then southwest from there. The cold front is lagging behind in fa

thunderman

thunderman

 

Severe Weather Threat Wed

An area of low pressure with move out of the plains and up to our Northwest. As it passes by, it will drag a fairly healthy cold front across the area Wednesday afternoon/evening. It is only January but strong winds just off the surface leading to strong shear, a good quality warm sector, and linear forcing with the front may be enough to trigger a strong to severe line of forced convection along the cold front. The primary threat would be damaging winds and heavy rainfall with PWATS possibly

thunderman

thunderman

 

First Decent Severe Event of The Season?

I eluded to the severe weather threat briefly in my more board centered post on the freezing rain/sleet potential a bit ago, but I thought that it deserved its own post given that it may be first real large (on an area scale) event. Area of interest is to the right of a line from the Akrlatex region to southern Indiana/Illinois to Western TN to the Gulf. The same synoptic trough out west that helps to setup our boundary will also be responsible for driving a low from the central plains up towa

thunderman

thunderman

 

Ice Sunday Night?

A warm front associated with the next system out west will cross the area Sunday night/Monday. The associated precipitation is expected to be very light ... with well under 0.25" very likely. Cold air at the surface looks marginal, with upper 20s at the lowest and with southerly flow around high pressure to the East, that will be kicked out fairly quickly IMO. Any precipitation that does fall will be in the form of sleet and freezing rain initially, with precipitation after roughly 13z likely

thunderman

thunderman

 

VIL Of the Day

Hail can be a weather enthusiast delight during the Summer time (perhaps it reminds them of snow?). Unfortunately, forecasting hail size can be a bit of challenge. One method that I use is VIL Of the Day (VOTD). It was developed by the NWS back in the 90s. It purely relies on temperatures aloft and while simple, does a surprisingly good job. Obviously there are some limitations, but I will get to those in a minute. The calculation is straight forward and is as follows: VOTD = 750 / [(h5T+h

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thunderman

 

Snow Chances Monday Night and Tuesday

Sorry I have been MIA over the last couple of weeks ... I spent the holiday with fiancee in PA (btw, the 12/29 storm was fun!) and then caught some kind of crud/flu that I have been fighting since the first of the year. This upcoming "event" is actually the most I have looked at anything weather-wise since the new year. Anyways, there are some rumblings of a potential snow or mix event for the Monday night and Tuesday time frame. Precip is expected Monday Night and Tuesday with a secondary wa

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thunderman

 

Low stratus/fog Keeping Temps Down For Some

Low status/fog has been hanging out all day across some portions of MD, Extreme Northwest VA, and Eastern PA. The result has been a near 20 degree temperature gradient across west-central VA and southeast PA! Some current temps as of 4PM across the area: KSHD 67 (High unofficially 69) KOKV 55 (High unofficially 61) KIAD 60 (High unofficially 62)

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thunderman

 

Introduction

I just want to take a few minutes outline the areas that I will be posting about and to introduce myself as I do not post much in general and rarely really post outside of the Mid Atlantic forum. I have been a member since the Eastern era of the board and have been tracking the weather as an enthusiast since the early 2000's. I moved to Southeastern PA to go school at Millersville in August 2008 and graduated from there with a B.S. in Meteorology in 2011. I enjoy forecasting in general and es

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thunderman