Saturday, July 26, 2014

Louisville Included in Moderate Risk for Severe Weather


Latest update from SPC...Moderate risk has been dropped due to lack of confidence in the development of MCS. ..Like I said before, always a tough thing to forecast several hours ahead of time. However, most of the same areas are still running with a high-end slight risk with damaging wind the primary threat. The atmosphere is juiced and the radar is already lighting up .

UPDATE 12:40pm
Latest update from SPC...Moderate risk backed off for a few more locations. However, models are continuing to diverge on expected solutions. Many factors still unclear. Again, these types of storm systems are always tough to forecast ahead of time. We really will not know how to forecast this thing until after the cap erodes later this evening and the actual complex begins to form.

UPDATE 11:45am
Warm front pushing through Louisville shortly. Dew points in low 70's in western KY. We'll feel it as soon as southwest winds kick in....

UPDATE 11:30am
Louisville out of moderate risk for now from SPC...However, uncertainty continues as to timing, formation, and location of well-advertised MCS. Since atmospheric conditions will become ripe for severe weather development, I think it's a good idea that the entire region is alerted to the very real possibility of severe storms, especially in areas that may be impacted overnight.

Another update from SPC due soon....

From the SPC, confidence is high that a significant severe weather event will be realized. Primarily, areas just north of the Ohio River across southern and central Indiana stand the best chance of seeing rough weather.

However, Louisville is included in a 45 percent hatched area for wind damage albeit barely.

It will be interesting to see how the numbers for severe weather will play out later this evening. We haven't seen too many overnight severe episodes in quite a while for Louisville.

Keep in mind, these MCS type storms are always very tricky to forecast ahead of time. So far, these are just computer-modeled forecasts. We really will not know how bad it could get until AFTER the complex begins materializing.

If the storms do in fact form, a significant wind event will be quite likely as winds could easily exceed severe criteria of 58 mph in many areas. Isolated spin-ups within the complex and along a bowing segment are possible as well.

More updates due later this morning.


Friday, July 25, 2014

Severe Chances Going Up

The Storm Prediction Center continues to advertise a possible widespread damaging wind event for Saturday. At this time, the highest chance for severe weather appears to lie across central Indiana and Illinois.

Will these storms maintain their strength as they approach Kentucky? Still, a lot of variables to look at, but Kentucky does appear to be within the area of instability to support at least a chance for damaging winds.

Stay tuned....


El Nino Off to a Late Start???

It's been advertised as possibly the biggest one yet. However, just like a well-hyped meteor shower, the initial sizzle of the upcoming strong El Nino is now looking more like a fizzle.

According to the latest news reports, El Nino has been slow to develop and is now forecast to be weaker than the prior forecast.

California generally benefits from El Nino's presence every 2-7 years during the late fall and winter periods. Often, excessive rains alleviate long-term drought as a parade of storms impact the west coast.

At other times, a Pineapple Express' moisture fetch benefits California as the Polar Jet becomes split upon encountering a blocking High near Alaska. The southern part of the split combines with the subtropical jet stream and is driven from the region near Hawaii (thus Pineapple) all to way to the western U.S coastline. The Madden-Julian Oscillation is an important parameter with this event.

El Nino Discussion


Friday, July 18, 2014

Forecasting Hurricane Intensity...A New Tool

A better understanding of hurricane development and intensity has been a primary focus for atmospheric scientists and engineers over the last several years. In Miami, home of the National Hurricane Center, operational facilities at Florida International University and the University of Miami are making 'waves' by means of state-of-the-art simulations both to help engineers build more water and wind resistant structures and weather forecasters understand how hurricane intensity forecasts can be more accurate.

For example, at the University of Miami's Rosenstiel School of Marine and Atmospheric Science, numerical simulations are being developed and analyzed to show that changes in the physical stress at the ocean surface, such as sea spray and foam and their evaporation,  may help explain the rapid intensification of some tropical storms.

In June 2012, ground breaking on a new Marine Technology and Life Sciences Seawater Complex began that promised to give scientists a new tool in simulating hurricanes within a controlled laboratory.

The large aquarium measures about 65 feet in length and 20 feet in width and 6.5 feet in height.

The simulator, called SUSTAIN, or SUrge-STructure-Atmosphere INteraction laboratory is the only facility capable of creating category- 5 level hurricanes in a controlled, seawater laboratory.

Also, Florida International University's Wall of Water (WOW) simulator cranks winds up to 157 miles per hour that helps test hurricane resiliency of varying structures from private homes to light poles. This simulator uses twelve 700-horsepower fans and  has been operational since 2012, in commemoration of the 20-year anniversary of Hurricane Andrew that devastated much of south Florida.