The Texas Department of Insurance (TDI) sent a team of fraud investigators to the area to deter any criminal element drawn to the scene after this week’s storms. Companies have declared the storm a catastrophe and are sending in additional adjusters to handle the claims. Amanda Bell with the Davis Body Shop in Odessa said everybody was swamped from last week’s storm, especially the glass companies.īoth homeowners and vehicle owners are urged to assess the damage to their property and contact their insurance companies as soon as possible. “We’ve had hail as large as 4 and a quarter inches and wind gusts near 70 miles per hour reported in both Midland and Odessa and in adjoining counties,” said Lister.Īuto body shops in the area were expected to fill up quickly with damaged cars. “We’ve been hit with large hail the last two days and last night was especially hard and we are supposed to get hit again tonight.”Īlex Lister, senior forecaster with the National Weather Service in Midland, said grapefruit size hail was reported one mile south of Midland while baseball size hail was reported in Odessa. So a basball sized stone, with a terminal speed of 80 MPH, would require a minimum updraft of (80 x 1.5) about 120 MPH.“It’s been nuts,” said Andrea Hidalgo with the Tara Simmons Insurance Agency in Odessa. This is roughly 50% to that of the stones terminal free-fall speed. To effectively allow a large stone to grow, the hail must be bbrought above and below the freezing level and to very high altitudes (around 20,000 feet), with deviations between 10,000 and 40,000 feet ocurring very quickly and in a timely manner to allow maximum growth with little melting.
The speed isīelow is a table for stones and their approximate terminal airspeed as MSLP. Smaller stones up to grapefruit size show the biggest terminal velocity differences as size increases, but not much past that. In other words, if a beachball sized hail stone was found, it will not fall more than about 120 MPH. This is why a pebble falls slower than a boulder at terminal speed (in air, not vaccuum) because the pebble (although made of rock also) has a higher drag ratio due to the boulder. Note: Hail stone fall rate is not related to the size of the stone but to the weight-to-drag ratio of it. Largest (recoerd breaking events, such as 5"+ in Wisconsin in June 2007 or 6"++ in Nebraska in June 2003) can approach 120 MPH (that's about the upper limit, similar to a human in free-fall (skydiving), as hail is composed of water, (or mostly water) like a person). Grapefruit sized (4") or larger would have a velocity of about 105 MPH. I'd do a quick search of AMS publications to help you out, but I need to head out.Īs with supercell updrafts, speeds of 150 to 175 MPH are not un-common.Ī large hailstone (baseball sized / 2.5") has a terminal velocity of about 80-85 MPH. I've remember hearing ~90 mph updraft to product a baseball-sized hailstone (though, again, there are many complicating factors, not the least of which is the effect of melting that occurs as a stone falls from the freezing level to the ground), but I can't give you any more specifics. I know this isn't exactly what you were asking, but I figured I'd mention it anyway. Add in hail trajectory differences, and you get a complicate picture. no meso and typically in weaker shear) with the same 2000 j/kg CAPE. Regardless, the role of the vertical perturbation pressure gradients helps explain why a supercell (with a meso, by definition) in an environment of 2000 j/kg CAPE (for example) can produce much larger hail than a multi-cell cluster (i.e. Typically, while SQRT(2*CAPE) can be an estimate of velocity, it's often seen that actual updraft velocity is 1/2*(SQRT(2*CAPE)) owing to invalid assumptions used in parcel theory (i.e.
Vertical perturbation pressure gradients (a function of the vertical wind and shear profiles) can have just as great a contribution to the updraft velocity as CAPE does.
In addition to what Paul wrote, it's important to remember that CAPE / thermal instability is only ONE contributor to updraft intensity.
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