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Substantial drought relief rains en-route?


Ginx snewx

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Nice steady light/mod RA since 5P yesterday IMBY, for 1.2" added to the tiny bit from the CF Sat night. Radar has a few more nice patches upstream, so a total near 2" seems likely, nice job of steering between not enough and too much. 7A temp was only 34 at my place, and 32-33 at 5A, but no signs of any slush/IP. Cocorahs report from 8 miles west and 300' higher had 0.1" SN/IP. Not as many folks in Maine live above 1,500' (most are in/near Rangeley) as in VT/NH, but I imagine their ground is white this morning.

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Maybe, but seems a little weird for that whole area to be graupel when so close to the beam. CC doesn't really show anything...could just be +RA.

Yeah it seems unlikely that's graupel.

One of the big problem with hydrometeor classification using dual pol parameters with horizontal scanning radars is that there is significant overlap in the ranges of different precip types. If you have a bayesian inferencing (or neural networking) component of your algorithm that ingests non-radar sensor data for situational awareness you can do a lot better job in the regions where it's unclear. But for my money if you want accurate precip classification using only radar data you really need vertical scans. Of course the huge drawback there is you only are classifying it in a single location, right over the radar.

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Yeah it seems unlikely that's graupel.

One of the big problem with hydrometeor classification using dual pol parameters with horizontal scanning radars is that there is significan overlap in the ranges of different precip types. If you have a bayesian inferencing (or neural networking) component of your algorithm that ingests non-radar sensor data for situational awareness you can do a lot better job in the regions where it's unclear. But for my money if you want accurate precip classification using only radar data you really need vertical scans. Of course the huge drawback there is you only are classifying it in a single location, right over the radar.

Yeah and you can always cross check it too with different parameters which is nice. Should be cool to use this summer with tstms and hail cores.

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nice rains, wind was never an issue or very much fun, and actually went south instead of the forecasted east here. Warm and humid out there right now, rains done..........now the pinwheel of pain, low 60s all week with breaks of sun. Is it ever going to get below normal..........EVER?

KFS is gonna rock you biatch

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nice rains, wind was never an issue or very much fun, and actually went south instead of the forecasted east here. Warm and humid out there right now, rains done..........now the pinwheel of pain, low 60s all week with breaks of sun. Is it ever going to get below normal..........EVER?

KFS is gonna rock you biatch

Sure has rocked lately. Dry begets dry.

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Yeah it seems unlikely that's graupel.

One of the big problem with hydrometeor classification using dual pol parameters with horizontal scanning radars is that there is significant overlap in the ranges of different precip types. If you have a bayesian inferencing (or neural networking) component of your algorithm that ingests non-radar sensor data for situational awareness you can do a lot better job in the regions where it's unclear. But for my money if you want accurate precip classification using only radar data you really need vertical scans. Of course the huge drawback there is you only are classifying it in a single location, right over the radar.

What were the scans of differential showing at the same time, maybe small hail?

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What were the scans of differential showing at the same time, maybe small hail?

I didn't see the raw display, however my guess is that some combination of fairly high Z and fairly low ZDR led to a faulty classification, and that it was most likely rain.

One would expect fairly weak updrafts as compared with a typical thunderstorm which would normally produce that level of reflectivity.

Therefore the droplets, while dense, are not particularly large, and take on a more spherical shape than the oblate "pancake" shape associated with T-Storms. Spherical droplets have lower ZDR, as does hail or graupel. Both of these may or may not actually be spheres, but they tumble in the atmosphere, so at any given moment the ratio of the Zh/Zv tends toward 1:1. So when I mention overlap, you have a table of Z & ZDR, and possibly CC as well, and with the values shown it could really be either rain or graupel, but when you consider the nature of the weather system, the temp profiles, etc., you'd probably lean toward rain.

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I didn't see the raw display, however my guess is that some combination of fairly high Z and fairly low ZDR led to a faulty classification, and that it was most likely rain.

One would expect fairly weak updrafts as compared with a typical thunderstorm which would normally produce that level of reflectivity.

Therefore the droplets, while dense, are not particularly large, and take on a more spherical shape than the oblate "pancake" shape associated with T-Storms. Spherical droplets have lower ZDR, as does hail or graupel. Both of these may or may not actually be spheres, but they tumble in the atmosphere, so at any given moment the ratio of the Zh/Zv tends toward 1:1. So when I mention overlap, you have a table of Z & ZDR, and possibly CC as well, and with the values shown it could really be either rain or graupel, but when you consider the nature of the weather system, the temp profiles, etc., you'd probably lean toward rain.

Thanks, last night I was wondering if we got a secondary popping along CC that headed past Boston into Maine, looks like it did, sort of a similar setup to the 2010 storm when NYC was dumping snow while all of NE was rain. That storm spawned a vicious secondary meso that caused huge wind damage. Cool look to the visible

2a45be78.jpg

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