Mission #8: A Quick Trip to the South Shore

The DREAMS Project celebrated the end of the month of June by having Mission #8 on Sunday, June 30th. The forecast was for scattered thunderstorms and the impromptu decision was made Sunday morning to try our luck at Smith Point beach in Mastic Beach. The students spent a couple hours with the DOW before wrapping up the quick mission. During that time they were able to scan two areas of weak, scattered storms. Something is better than nothing according to our optimistic sides!

The DOW left Stony Brook University around 2:00 PM and was set up to start scanning by 3:00 PM. There had been some fog at Smith Point but it had lifted a bit upon our arrival. The students were first able to sample some showers and thunderstorms to our northwest. After identifying the area of higher reflectivity with the horizontal scan, they chose to do vertical slices to see the semi-3D structure of the cells.

The DOW at Smith Point ready to start sampling nearby showers and thunderstorms.

Have you noticed that most posted photos of the DOW have the truck on what appear to be stilts? The DOW6 is equipped with 5 hydraulic feet that can have varying heights to make the DOW level on uneven surfaces. Why is this important? With a radar beam of energy coming and going from one point and moving in a circle and even up and down, there's a lot of math involved (especially trig)! To simplify the calculations, the DOW is leveled in reference to the ground that it is sitting on. This also ensures that the radar beam isn't being transmitted at really odd angles and completely missing storms. For the quality of the data, it makes sense to have it level if the DOW is going to be in one place. However, the data is perfectly fine if the radar is operated while the DOW is in motion. We haven't had much storm activity to actually need to operate the radar while in motion, unfortunately!

The level DOW using its hydraulic feet at Smith Point.

By around 4:00 PM an interesting single cell had fired up over the open ocean and was moving north-northeast. The students' attention thus focused onto this cell and they changed the orientation of the radar to take vertical slices of the cell instead of the activity to the northwest. Over the course of a couple hours, the cell grew and became more stratiform (i.e. a broader area of lighter rain versus convective which is heavier showers over a smaller area) before going out of range of the DOW. Interestingly enough, a group of very small-scale cells developed to the southwest of the original cell likely due to the fact that the original cell may have produced some outflow of cooler, denser air that forced air to rise above it. That may be how the cells were activated. At around 6:00 PM the mist began to thicken and cover anything exposed with water droplets. The students luckily all fit inside the DOW and paid attention to the developing fine-scale cells before wrapping up the mission at 7:30 PM. Despite being a quick mission, the students were able to become more comfortable operating the radar and with making decisions about where to selectively perform RHI, or vertical, scans through a particular area of higher reflectivity.

- For an inside look at how the different components of the DOW, please see this operations manual: http://somas.stonybrook.edu/downloads/DOW6OperationsManual.pdf
- For a near real-time update on where we'll be next, please see the DREAMS Project website: http://dreamsproject.weebly.com/schedule.html