Thanks Bryan! Nice travel disclaimer. 😉 Rob Raker Lakewood, CO
On Tuesday, May 5, 2020 at 8:59:39 PM UTC-6, Bryan Guarente wrote: > > I need to congratulate Luke and Tracy Pheneger for finding the Hermit > Warbler in Melody Tempel Grove this morning! Great find! For me, this is > a great data point because bird migration in the Intermountain West is a > messy world. This bird is a great data point! Let's analyze some of the > times before now and see what we can find out about the appropriate wind > patterns aloft to produce Hermit Warblers in CO. So again thanks to Luke > and Tracy Pheneger for finding the Hermit Warbler so I can write such a fun > post... > > All but three Hermit Warbler records in Colorado happens in the last week > of April or the first two weeks of May. This should lead you to look at > timing of Hermit Warbler migration, but also to ask the question (if I > haven't trained you well enough yet) of what makes these weeks interesting > for winds from Hermit Warbler territory? I cannot answer that question > easily aside from analyzing what is currently happening to get this Hermit > Warbler into CO. > > This warbler's story likely starts on May 3rd, but we cannot guarantee > what time, so here is a guess (feel free to look at the times around this > too to get an idea of what I mean): > > https://earth.nullschool.net/#2020/05/03/2100Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > (Green > Circle is Melody Tempel Grove for reference) > > The winds over the Desert Southwest (not knowing exactly where this bird > originated from we can only generalize) are broadly southwest winds and end > up traveling into southern CO. Over the next six hours, you can watch the > convergence of winds over SE CO to see that the SW winds are consistently > projecting into CO from the Southwest US. Let's watch this over time below > and I will walk you through what I see. > > 6pm Sunday: > https://earth.nullschool.net/#2020/05/04/0000Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > Continued SW winds pointing into southern CO with a convergence zone SW of > Melody Tempel Grove > > 9pm Sunday: > https://earth.nullschool.net/#2020/05/04/0300Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > Continued SW winds pointing into southern CO with a convergence zone now > *just* SW of Melody Tempel Grove > > Midnight Monday: > https://earth.nullschool.net/#2020/05/04/0600Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > At this time, there is likely a frontal passage near the surface that > likely grounds the bird due to northerly winds. > > 3am Monday: > https://earth.nullschool.net/#2020/05/04/0900Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > At this time, assuming the numerical model is correct, there would now be > a solid convergence over Melody Tempel Grove and birds won't likely move > from this location as the lowest pressure is upon them. > > 6am Monday: > https://earth.nullschool.net/#2020/05/04/1200Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > Continued Northerly winds holding the bird in place... and this pattern > continues through today (May 5th). > > This pattern loosely continues until 6pm May 5th (this evening) where > there will be a mixture of northerly and southerly winds since the grove is > right under the convergence zone again. This likely means VERY NICE > conditions at Melody Tempel Grove tomorrow May 6th. > > > https://earth.nullschool.net/#2020/05/06/0000Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > > Over the following forecasted 12 hours, it looks like the convergence > moves south of the Arkansas river into the Raton Mesa region of NM, but > this doesn't mean there won't have been the addition of birds in the > overnight hours. > > > https://earth.nullschool.net/#2020/05/06/1200Z/wind/isobaric/850hPa/orthographic=-102.78,38.22,1325/loc=-102.780,38.220 > > So, if you are in SE CO, keep your eyes peeled for an injection of more > birds (and likely convergence of birders). My prediction is this will get > better in terms of the density of birds at Melody Tempel Grove, or anywhere > along the Arkansas River. > > With how many Arkansas River forecast convergence zones I have predicted > so far, no wonder the folks down there love April and May, and why lots of > birders travel that direction to find nice migrants. Good luck down that > way! > > NOTE: This email does not mean you should break any laws or restrictions > from your local governments. > > Thanks and Great Find! > Bryan > > Bryan Guarente > Meteorologist/Instructional Designer > UCAR/The COMET Program > Boulder, CO > -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/5201b337-c1fc-4b51-a4bb-703ea5447128%40googlegroups.com.
