Max Posted November 20, 2013 Share Posted November 20, 2013 I wish I stuck with my initial HYSPLIT air parcel calculation of 40F ugh FML Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 Still no response from the Gray NWS office. Did you try Mike Ekster? He works there. I know a few others from a presentation I did there. I believe Mike is on the forums, but I'm not positive with his id. Could be Arnold219. If gray doesn't get back to you maybe you can pm him. Link to comment Share on other sites More sharing options...
weatherMA Posted November 20, 2013 Share Posted November 20, 2013 Did you try Mike Ekster? He works there. I know a few others from a presentation I did there. I believe Mike is on the forums, but I'm not positive with his id. Could be Arnold219. If gray doesn't get back to you maybe you can pm him. It's Arnold214 Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 It's Arnold214 Thank you. Link to comment Share on other sites More sharing options...
Mallow Posted November 20, 2013 Share Posted November 20, 2013 Did you try Mike Ekster? He works there. I know a few others from a presentation I did there. I believe Mike is on the forums, but I'm not positive with his id. Could be Arnold219. If gray doesn't get back to you maybe you can pm him. Ya, I've met Mike before. Is he at the Gray office now? I thought he was at the Taunton office before... Link to comment Share on other sites More sharing options...
Metsfan Posted November 20, 2013 Share Posted November 20, 2013 Hey Max. I am a little confused how HYSPLIT is calculated. Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 Ya, I've met Mike before. Is he at the Gray office now? I thought he was at the Taunton office before... I think he's been at the Gray office for a few years now. Don't know if he moved recently to the Taunton office if you think he did. But I just spoke to a friend still at LSC and he confirms that Mike is still working at the Gray, Maine office. Link to comment Share on other sites More sharing options...
Mallow Posted November 20, 2013 Share Posted November 20, 2013 I think he's been at the Gray office for a few years now. Don't know if he moved recently to the Taunton office if you think he did. But I just spoke to a friend still at LSC and he confirms that Mike is still working at the Gray, Maine office. No it would have been a while ago. I think I vaguely remember hearing he was gonna move to the Gray office now that you mention it. Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 Hey Max. I am a little confused how HYSPLIT is calculated. So when doing backward trajectories for any station, you need to pick a model that goes far enough out in time if you are trying to figure out the high temperature. Then select backwards for trajectories, input the date and time for when you think the high will be reached. Also make sure the hours the trajectories run for is correct or you will get an error. Afterwards input 3 parcel heights above ground level and it means above the station so if KCON is 103m, it doesn't add 103 meters to your inputs, it starts from 0. So once you have given HYSPLIT the model input, the time input, set the trajectory to backwards, and also picked 3 parcel heights, and those parcel heights are the ending heights keep in mind, then press start and you will get a gif image. So the 3 parcel heights need to be close to what you think the boundary layer height could be or else the calculation you do won't be correct. And usually I pick 1 of the 3, but sometimes if I'm not sure what the BL will reach I do an average of all 3. It's simply taking the parcel start and end heights, taking the difference, and adding that to the approximate surface temperature at the time the trajectory is over a certain point. So for example, if the parcel started over St. Louis, MO at 500m at the start of the model run and ended up over KCON at the end of the model run at 200m. Then using the dry adiabatic lapse rate you'd need to add 3C to the surface temperature at St. Louis to approximate the KCON temperature x hours later. This method doesn't work all the time because sometimes the parcel is over a sparse data region, or its not a straight line, or even simply its not going to be clear and sunny the next day. Lots of different things make this method not an exact science, but sometimes it works. Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 This is what I got for today's HYSPLIT using the 18z NAM for tomorrow. Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 So we have to pick areas other than kcon? No. Using this page link: http://ready.arl.noaa.gov/hypub-bin/trajtype.pl you leave the default settings alone and just click next. Then on this page link: http://ready.arl.noaa.gov/hypub-bin/trajsrc.pl you select one location using any of the ways listed. I just simply use the airport code, which for kcon, is con. Also select which model you want to use using the scroll down at the top. After that just click next. This link: http://ready.arl.noaa.gov/hypub-bin/trajsrcm.pl brings you to the model run, again use the scroll down and then click next. Lastly on this page link: http://ready.arl.noaa.gov/hypub-bin/traj1.pl Make sure to select backward, and then everything else should be self explanatory. And also make sure to keep maximum # of trajectories to 3. KCON is the end point to all 3 so you don't have to pick any other locations other than KCON. Link to comment Share on other sites More sharing options...
Metsfan Posted November 20, 2013 Share Posted November 20, 2013 OK, but in reading this output isn't it the same thing from extrapolating from a sounding? What does the ending trajectory mean? Does it mean where a person can extrapolate from a sounding? What does the red, blue and green lines mean? Thanks. Link to comment Share on other sites More sharing options...
Metsfan Posted November 20, 2013 Share Posted November 20, 2013 Going with 42/16/5/0 Link to comment Share on other sites More sharing options...
Max Posted November 20, 2013 Share Posted November 20, 2013 OK, but in reading this output isn't it the same thing from extrapolating from a sounding? What does the ending trajectory mean? Does it mean where a person can extrapolate from a sounding? What does the red, blue and green lines mean? Thanks. Those are the 3 different ending parcel heights. And soundings can't tell you where parcels are coming from. The jist of the HYSPLIT is finding where air parcels are going and coming from. It's kind of like saying if x parcel was at y and then ended at z 24 hours later without changing the temperatures at y and z 24 hours apart should be exactly the same if the parcel did not change. And also if the top of boundary layer for example was at 400m and you wanted to see where a parcel that ends up at 400m came from you can using the backwards trajectory function of the HYSPLIT. Hope this clears it up a bit more for you. I gotta go now so I won't be on until probably tomorrow. A Link to comment Share on other sites More sharing options...
Chrisrotary12 Posted November 20, 2013 Share Posted November 20, 2013 WRFs and HRRR are concerning.......don't even get the temp under like 20. But the winds should be calm for most of the night. Link to comment Share on other sites More sharing options...
L.B. LaForce Posted November 20, 2013 Share Posted November 20, 2013 Same deal last night. I think that's what threw off my 5 minute forecast. Models had the atmo decoupled, but refused to drop temps. 4km NAM, and HRRR are on crack attm it seems. Latest ob is at 26 with a 6hr low of 24 already. Link to comment Share on other sites More sharing options...
Chrisrotary12 Posted November 21, 2013 Share Posted November 21, 2013 I feel bad for this but my forecast is basically the USL. 43/13/5/0. I originally has 11, but got scared. Edit: And now I am kicking myself for not keeping the 11 that I had. Son of a....... Link to comment Share on other sites More sharing options...
OHweather Posted November 21, 2013 Share Posted November 21, 2013 43/9/9/0 The low for tonight will be interesting...they fell 5 degrees in the last hour and are already decoupled. Although most guidance is anywhere from 12 (NAM MOS) to 13 (USL) to the mid teens (GFS MOS), to go along with most raw models struggling to drop things below 20, things should be just about perfect for a good radiational cooling night in a bit of a valley. The NWS had 9 and after much thought decided to go all in with that number. The mean for tonight is 16F so anyone who went cold may really make up some ground...at least I hope so. Link to comment Share on other sites More sharing options...
wxmeddler Posted November 21, 2013 Share Posted November 21, 2013 46/14/7/0 Cell phone in class forecast. Link to comment Share on other sites More sharing options...
L.B. LaForce Posted November 21, 2013 Share Posted November 21, 2013 Models and human forecasters have been all over the place the last few days on WxChallenge. It's kind of funny to watch. Anyways, went 42/12/7/0. One more forecast to go (likely precip too) - next city please! Link to comment Share on other sites More sharing options...
wxmeddler Posted November 21, 2013 Share Posted November 21, 2013 It's funny.. I do well when models are not, and do bad when models are doing well. Perhaps a sub-concious distrust of models... Link to comment Share on other sites More sharing options...
Chrisrotary12 Posted November 21, 2013 Share Posted November 21, 2013 22 already but the dew point is up to 14....... Link to comment Share on other sites More sharing options...
Mallow Posted November 21, 2013 Share Posted November 21, 2013 45/11/6/0 Link to comment Share on other sites More sharing options...
H2Otown_WX Posted November 21, 2013 Share Posted November 21, 2013 46/9/8 I strayed from consensus to try to pick up some serious ground. Definitely nervous about the low with the dew point creeping up and I tore my hair out over the high. I could see it being lower but I feel like this is similar to last Thursday where the high was about 5 degrees higher than modeled. In this case, the NAM is on my side, at least until 00z MOS. Link to comment Share on other sites More sharing options...
Max Posted November 21, 2013 Share Posted November 21, 2013 I went 45/13/5/0. I feel like I should have stayed with 12. Link to comment Share on other sites More sharing options...
H2Otown_WX Posted November 21, 2013 Share Posted November 21, 2013 Oh hello high clouds, so nice of you to ruin my forecast. Link to comment Share on other sites More sharing options...
OHweather Posted November 21, 2013 Share Posted November 21, 2013 The clouds aren't overhead but the temperature drop seems to have halted for now...20 at 4z. Link to comment Share on other sites More sharing options...
ctsnowstorm628 Posted November 21, 2013 Share Posted November 21, 2013 18F at 5z. My 17F looks good. Maybe 16. Tomorrow I have 45/12/7. Might be higher than 12 at this rate. Link to comment Share on other sites More sharing options...
ma blizzard Posted November 21, 2013 Share Posted November 21, 2013 18F at 5z. My 17F looks good. Maybe 16. Tomorrow I have 45/12/7. Might be higher than 12 at this rate. 16 it is 46/14/8/0 for tmrw .. hoping the temp starts bottoming soon. potential is there with high clouds starting to move in Link to comment Share on other sites More sharing options...
ctsnowstorm628 Posted November 21, 2013 Share Posted November 21, 2013 Looks like 13 for a low. 3rd in this city with "max" killing it at number 1 by a good margin. Give me 45 and 7 for winds please! Link to comment Share on other sites More sharing options...
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