Evaluating storms across the Albany WFO this afternoon. Convection was already ongoing at the beginning of this evaluation, namely in a linear fashion. GOES-R satellite imagery proved to be useful in the initial analysis of synoptic scale features. A shortwave was noted to the north/northwest of the CWA via upper level water vapor, indicating that large scale forcing will likely aid in buoyancy. The 4 panel WV loop was very useful in an quick top down analysis, particularly moisture. Upper level shows the wave very well, mid level shows where deepest moisture resides and the lower level shows where the frontal boundary resides (taking this a step further we can also see convection generated right along the front vs the convection out ahead in the deeper moisture).

As for lightning, it was overall useful in helping to quickly address where the
stronger, more mature convection was at, however almost right away i found myself more drawn to watching the ENTLN trend because the GLM was displaced out ahead of the convection and seemed a little distracting. Top right shows the ENTLN and the top left shows the GLM.

As the line began to evolve, the NUCAPS sounding data came in. The original SNPP NUCAPS data seemed to largely underestimate the amount of instability (it was showing 100-200J/KG MLCAPE). Although I did not look at any model or SPC mesoanalysis data, based on the season, the forcing, and the amount of clearing ahead of the convection, this seemed very unrealisitic. I plotted the experimental SNPP to compare and this data seemed MUCH more reliable, showing over 2000J/KG of MLCAPE. I felt more comfortable using this data.  I then completely discounted the original SNPP data.

I find the PROBSevere to be very useful as an aid to the real time meteorology. It, for me, was more of a reassurance product as I noticed cloud tops cooling or lightning increasing, radar imagery changing, etc. I normally do not like to use derived products such as this, but I REALLY like the fact that I can see the values of each parameter that goes into it (which is probably a big reason why I decided to use it in the first place). I think almost all of the forecasters at FFC would love to use this product.

As the storms continue to evolve over the course of the afternoon, the evolution of the clouds really show up well in the IR imagery. However, it is frustrating when the last frame in my loop doesnt load the full image. Sometimes the loop can be jumpy too, which is really annoying

When looking upstream the "sandwich" imagery proved very useful in revealing some merging outflow boundaries across PA. This alerted me to the possibility of strong convection moving in later this afternoon. Will continue to monitor trends

Watching the evolution of the storms across NE PA, The IR still seems to be doing a good job of showing how the storms are evolving/which ones are strongest. This really coincides well with where the PROBSevere is showing the highest threats. PROBSevere is quicker to analyze find trends than looking for increases in lightning.

Storm evolution overall in the Albany WFO has been of the pulse-variety today, with really two strong/severe storms. This is similar to what we see at FFC this time of year, so I'm really enjoying testing all of these products. Towards the latter portion of the afternoon, convection weakened, with most storms back building from NE PA into central PA.

NUCAPS soundings from FGF area...

Showed a warm layer above 700mb in several soundings from northeast SD/west central MN around 19Z. This may have contributed to storms seemingly struggling to organize during the first couple hours after initiation.

Operational Helper

If possible, being able to create time series of GLM, MESH, GOES 16 data over a user defined area would be very helpful. While a storm tracking type area would be great, even a simple hand drawn polygon type application to identify areas to create time series would be very useful.

The following image, I think shows the need for this type of functionality. When storms become numerous, becomes difficult to figure out what storm is contributing what data to the lightning totals.

-JRM

2032-2037 UTC Grand Forks CWA - Storm near Perham

At 2027 UTC storm near Perham showed a strong decrease in cloud top temperatures as indicated by GOES-16 Clean IR imagery. Values fell to -66.4 C at this time, with a gradual warming to -60 C by 2037. At the end of the loop below, another strong updraft pulse was noted with a minimum temperature of -69 C. Point soundings for a mixed layer parcel via the RAP suggest equilibrium temperatures around -50 C.  GLM Data also indicated an increase in storm intensity. At 20:27 UTC 191 GLM flashes were indicated,  this climbed to a max of 242 by 2030 UTC. The biggest minute to minute change occurred at 2029 UTC with an increase of 34 flashes in a minute.

2027 Satellite/Radar comparison showed how important using radar data to fine tune the location of the actual storm when using GOES data. The paralax error in position was apparent in the images below. Note where Perham is for a spatial reference.

-JRM



-JRM

1957 Grand Forks Storm Intensifing

At 1957 UTC GOES 16 IR imagery indicated cloud top temperatures of -58.8 C, colder than the estimated equilibrium level temperature of -51 C.  An increase in GLM flashes was noted just 1 minute prior at 1956. Over 316 GLM flashes occurred in the 5 minutes ending just before the decrease in cloud top temperatures. 

-JRM

GLM update for northern plains

GLM has shown a substantial uptick in lightning activity over the last 15 minutes, coincident with strengthening convection in far southeast ND and west central MN. ProbSevere is up above 50 percent on this storm, however the increase in lightning activity preceded the storm being identified on prob severe.

Storm is also taking better reflectivity structure and may need a warning soon.

-64BoggsLites

Grand Forks 1930 UTC Forecast Discussion

Thunderstorm development and severity will be primary forecast concern, mainly across southeast portions of the Grand Forks CWA.  1712 to 1902 UTC GOES-16 visible satellite loops indicate two areas of concern for potential convective development. The first along a trough axis extending southeast from KBWP and along weak warm front in localized area of H85 WAA.

SPC objective analysis indicated around 2000 j/kg of MLCAPE with little CINH along southward extending trough...but increasing to the north and east near the warm front.  RAP forecast soundings indicate similar values will continue through 23 UTC. Effective shear values around 35 kts were indicated in this area. Shear and instability will remain favorable for some supercells with low level shear increasing near warm front where low level shear increasing near warm front, indicating at least a small tornado risk

 By 19427UTC, convective invitation underway with cloud top temps reaching around -52 C with cells just to the west of sfc trough.

-JRM

Grand Forks 19z Satellite discussion

Simple water vapor imagery depicts a weak shortwave trough lifting through eastern ND this afternoon, and although this feature is noted in the low, mid, and high level WV imagery, it's much more subtle in appearance in these 3 channels.

Visible imagery shows a boundary dropping south through central MN currently, and there has been an increase in CU along this boundary as it pushes south. This area in far southeast ND into northeast SD and west central MN seems primed for surface based convection within the next couple of hours.

Also noted in the airmass RGB were differences between the the more moisture rich airmass within the warm sector, which appeared with more of a green hue, while the airmass further west across the western Dakotas is drier based on surface observations, and had more of a red hue.

-64BoggsLites

Opening day

One of the first things I noticed was the displacement of the GLM from the storm cores. The lightning as indicated was not in locations I would expect - did not match up with the location of the storm cores indicated in ProbSevere/NEXRAD... nor was there much agreement with CG locations from NLDN.

Watching line of convective storms moving through Albany CWA. Tested the SNPP NUCAPS sounding. The legacy product showed very low SBCAPE 349 (2) ahead of approaching squall line, as surface temp was cooler than surrounding obs. Manually corrected the legacy sounding to nearest ob, and increased the SBCAPE to approximately 2000 j/kg. Waited another few minutes and when the experimental NUCAPS sounding came out (2), the same location (nearest point Charleston 4 Corners) already included the warmer surface temperature, and resulted in a SBCAPE of 2804.


    (1)                                                                (2)

Watched a line of thunderstorms move into this area. ProbSevere wind increased from 40%  to 54%. Noted velocity on KALY radar. I issued a warning for wind threat, leaning heavily on ProbSevere trend upward.



Squall line moved into the box, and ProbSevere wind increased in time, 57% to 72% to 75%. 



During this time, at least three LSR's were produced:

(08:48:33 PM) nwsbot: Local Storm Report by NWS ALY: Charlton [Saratoga Co, NY] 911 call center reports TSTM WND DMG at 04:19 PM EDT -- wires down. time estimated by radar.
(08:51:07 PM) nwsbot: Local Storm Report by NWS ALY: Ballston Center [Saratoga Co, NY] 911 call center reports TSTM WND DMG at 04:31 PM EDT -- downed tree.
(09:00:08 PM) nwsbot: Local Storm Report by NWS ALY: Amsterdam [Montgomery Co, NY] facebook reports TSTM WND DMG at 04:01 PM EDT -- reports of two downed trees in amsterdam. one on truax road and second near intersection of church street and cornell street.

As squall line moved out of my box, I had to decide what to do with it. Based upon ProbSevere trend, and as my partner pointed out, lightning trend diminished, I downgraded to SPS.



I issued SPS for 30 minutes, and there was one LSR generated during the valid time...

 (10:28:49 PM) nwsbot: Local Storm Report by NWS ALY: Clifton Park [Saratoga Co, NY] 911 call center reports TSTM WND DMG at 04:51 PM EDT -- trees down.

... but actually the line diminished in intensity very quickly a few minutes later.

It appears that if a forecaster had used ProbSevere only, they would have done just fine in handling this event.

Two issues that affected satellite usage:
-Data unavailable due to cloud cover from neighboring convection
-Concerns about using satellite data in specific locations due to satellite displacement of features


-tvguy

Week 4 Day 1

The last week of the GOES-R/JPSS Experiment is underway in the HWT. Today forecasters will be operating in the Albany, NY and Grand Forks, ND CWAs.

Michael