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RAMM BRANCH WEEKLY HIGHLIGHTS FOR THE WEEK ENDING July 12, 2018IN THE MEDIA: GeoColor from RAMMB SLIDER used by Washington Post: The Washington Post’s Capital Weather Gang featured a GOES-16 GeoColor image taken from RAMMB SLIDER in an article () on Tropical Storm Chris that is off of the east coast of the US. While the impacts of rain and wind will remain off the mainland, the article discusses the potential for “dangerous rip currents” from South Carolina to the Delaware-Maryland border. Chris would go on to intensify to a 90 kt category 2 hurricane on the Saffir-Simpson scale before racing northeast and undergoing extratropical transition. (C. Slocum, CIRA, 970-491-8446, Christopher.Slocum@colostate.edu)ITEMS FOR THE ADMINISTRATOR:ITEMS FOR THE ASSISTANT ADMINISTRATOR:ITEMS FOR THE OFFICE DIRECTOR, STAR:ITEMS FOR THE DIRECTOR, CoRP:Assimilation of All-sky Radiances into the Operational HWRF Model: One main goal of the Sandy Supplemental project was to assimilate all-sky radiances into the operational HWRF model. As of now, when HWRF is started no condensate and no vertical motion exists at the initial state. As a result of all-sky data assimilation, a non-zero condensate field is initialized; however, no vertical motion exists. As a consequence of no vertical motion, condensate may simply precipitate/sediment downward. That is, precipitation/sedimentation represents a sink to the condensate field. In Fig. 14, the initial condensate field is shown at the 35th model level (Fig. 14a). However, 5-min. later (Fig. 14b), a noticeable decrease in condensate was evident in the northern half of the storm. As the HWRF forecast continued past 15-min (Fig. 14e) and 30 min (Fig. 14f) mostly all of the condensate settled downward effectively negating the benefit of all-sky radiance assimilation. An important recommendation to the HWRF developers is to update HWRF by allowing non-zero vertical motion at the initial time in an attempt to be compatible with the inclusion of condensate via all-sky radiance assimilation. (L. Grasso, T.-C. Wu, K. Musgrave, and J. Knaff E/RA1 970-491-8446: Lewis.Grasso@colostate.edu, Ting-Chi.wu@colostate.edu, Kate.Musgrave@colostate.edu, John.Knaff@)CIRA Layered Precipitable Water Products Evaluated at WPC Flash Flood and Intense Rainfall (FFaIR) Experiment: CIRA produces and distributes to national centers and partner WFOs a 4-layer precipitable water (LPW) vapor product derived from passive microwave retrievals on polar orbiting satellites. This product is commonly referenced in WPC Mesoscale Precipitation Discussions (MPDs) to alert WFOs to flash flooding potential. An example of the advected LPW product is shown in Figure 1.Figure 1: 4-layer advected precipitable water at 15 UTC July 11, 2018.The next step with this product is to see how it compares to model water vapor fields. This information can be used by a forecaster to assess whether the model forecast is too moist or too dry and then adjust the precipitation forecast accordingly. CIRA is participating in the 5-week Flash Flood and Intense Rainfall experiment (FFaIR) at WPC to evaluate the difference between the HRRR model and the CIRA LPW product. An example difference field is shown in Figure 2, showing the HRRR LPW minus the CIRA LPW. Green / blue regions indicate the model is moister, while brown / red regions indicate the model is drier than the CIRA LPW. These fields are being evaluated during FFaIR by the team of about a dozen forecasters and scientists and results will be summarized in the final FFaIR report. Model difference work is supported by the NOAA Hydrometeorology Testbed, while production of CIRA LPW is supported by the JPSS Proving Ground and Risk Reduction program. (J. Forsythe, CIRA, 970-491-8589, john.forsythe@colostate.edu)Figure 2: Operational HRRR 3-hour forecast layer precipitable water minus CIRA LPW (mm) valid at 15 UTC 11 July 2018.New Near Constant Contrast (NCC) Quick Guide: Apart of the Satellite Foundational Course for JPSS (SatFC-J), a NCC Quick Guide (1-2 page document) has been developed for NWS forecasters. Quick guide encompasses the primary applications and limitations of the NCC product, while highlighting the NCC imagery enhancement techniques in AWIPS. The document can be accessed in two ways: via the NOAA VLAB for NWS forecasters, and through the CIRA/VISIT training webpage for non-AWIPS users (refer to the following link). (J. Torres, E. Dagg, B. Connell, 970-491-8446: jorel.torres@colostate.edu, Erin.Dagg@colostate.edu Bernie.Connell@colostate.edu)Positive feedback on rapid intensification aids: The Rapid Intensification (RI) forecast guidance aids recently added to the Joint Typhoon Warning Center’s guidance suite performed well for Typhoon Maria. We received positive feedback and a graphic from NRL Monterey. The graphic below shows the deterministic forecasts triggered by the RI guidance. It’s a messy plot, but it clearly shows the guidance was triggered prior to Maria’s rapid intensification. (J. Knaff, E/RA1, 970-491-8446, John.Knaff@)Caption. Graphic received from NRLMRY at 02 UTC 4 July during the RI of Typhoon Maria. RI25, RI30, RI35, RI40 are forecast increases of 25, 30, 35, 40 kt in 24 h, RI45 and RI55 are forecasts of increases of 45 and 55 kt in 36 h and RI70 is a 70 kt increase in 48 h. Deterministic forecasts are triggered when probabilities of that threshold being exceeded are greater than 40%. Of note, Maria reached its first peak intensity of 140 kt at 00 UTC 6 July. Manuscript published online: The manuscript entitled “Statistical tropical cyclone wind radii prediction using climatology and persistence: Updates for the western North Pacific” by J. Knaff, C. Sampson (NRLMRY), and K. Musgrave and discussed last week was published in the Early Online Release of Weather and Forecasting. . (J. Knaff, E/RA1, K. Musgrave, CIRA, 970-491-8446, John.Knaff@, Kate.Musgrave@colostate.edu)SLIDER Server Traffic for First Full Year: The SLIDER server that was publicly launched in late June of 2017 has received significant traffic in its first full year. From 1 July 2017 through 30 June 2018, the site was viewed by 463,878 unique visitors for a total of over 1.2 million sessions. Just slightly more than 50% of the traffic came from the US, with Eastern Asia and South and Central America making up large portions of the remainder. Major spikes in traffic occurred during multiple events, primarily during the very active 2017 hurricane and fire seasons. Over the course of the year, users came to the site for an average of over 3,500 sessions per day. (K. Micke, CIRA, 970-491-8446, Kevin.Micke@colostate.edu)Figure: Detailed statistics, aggregated by week to smooth out traffic spikes, for the SLIDER server from 1 Jul 2017–30 Jun 2018.Figure: Map of countries from which users accessed the SLIDER server from 1 Jul 2017–30 Jun 2018. Figure 3: Detailed statistics of the top ten sub-continental regions from which users accessed the SLIDER server from 1 Jul 2017–30 Jun 2018.Presentation: Steve Miller, John Haynes, and Y. J. Noh attended the FAA Aviation Weather Research Program (AWRP) Review Meeting (10-11 July 2018, Boulder, CO). Steve Miller delivered an oral presentation, titled “Aviation-Relevant Satellite Research and Algorithm Development at CIRA.”(S. Miller, J. Haynes and Y.-J. Noh, CIRA, 970-491-8446: Steven.Miller@colostate.edu, John.Haynes@colostate.edu, Yoo-Jeong.Noh@colostate.edu)Figure: Steve Miller giving a presentation at the FAA Aviation Weather Research Program (AWRP) Review Meeting (10-11 July 2018, Boulder, CO)Manuscript Reviewed: L. Grasso reviewed a manuscript for Weather and Forecasting. (L. Grasso CIRA, 970-491 8446: Lewis.Grasso@colostate.edu)VISITORS: Nothing to ReportNEXT WEEK: Nothing to ReportLOOKING AHEAD: Nothing to Report ................
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