Spot Forecast
Issued by NWS Boston, MA
Issued by NWS Boston, MA
505 FNUS71 KBOX 290740 FWSBOX Spot Forecast for Herman Covey WMA Grasslands RX Burn...MassWildlife National Weather Service Boston/Norton MA 340 AM EDT Wed May 29 2024 Forecast is based on ignition time of 0500 EDT on May 29. If conditions become unrepresentative, contact the National Weather Service. .DISCUSSION... A sunny and dry start to the day, though scattered showers and thunderstorms develop as early as 12pm to 2pm. Confidence in any strong to severe storms is greatest for locations south and east of the prescribed burn. Storms that develop in the area of the prescribed burn likely remain sub-severe, though lightning remains a threat with any storm this afternoon. Showers and thunderstorms dissipate early evening. A second round of rain is possible late night into late morning Thursday, with more widespread rainfall possible. Rain comes to an end second-half of Thursday followed by drying conditions. .OUTLOOK...Friday through Monday... High pressure building in from the west will bring mainly dry and very pleasant weather Friday into the weekend. .TODAY... Sky/weather.........Mostly sunny. Slight chance of rain showers in the afternoon. Isolated thunderstorms late in the afternoon. CWR.................9 percent increasing to 29 percent late in the afternoon. Max temperature.....Around 76. Min humidity........46 percent. Dewpoint............53. Max apparent temp...74. Surface winds (mph).Northwest winds 5 to 7 mph. Wind (20 ft)........Northwest winds 5 to 7 mph. Gusty and erratic winds expected near thunderstorms late in the afternoon. Mixing height.......6700 ft AGL. Transport winds.....Northwest 6 to 8 mph. Smoke dispersal.....Poor (5300 knot-ft) early in the morning increasing to good (47000 knot-ft) in the afternoon. LVORI...............3. ADI.................8 to 17 increasing to 27 early, then increasing to 38 late in the morning increasing to 48 to 54 decreasing to 31 to 38. Haines Index........3 or very low potential for large plume dominated fire growth. CEILING (KFT).......13 decreasing to 6.0. TIME (EDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........38 37 36 42 48 55 57 59 61 60 59 58 Weather cov..... SCH SCH SCH SCH SCH Weather type.... RW RW RW RW RW Tstm cov........ ISO ISO ISO ISO CWR.............0 0 10 10 10 10 10 10 30 30 30 30 Temp............57 59 62 64 67 69 71 73 74 74 73 72 Dewpoint........53 54 54 53 53 52 52 52 53 52 52 52 RH..............86 83 75 67 61 55 51 48 48 46 48 49 Heat index (F)..57 59 62 64 67 69 71 73 74 74 73 72 20 FT wind dir..NW NW NW NW NW NW NW NW NW NW NW NW 20 FT wind spd..5 6 7 6 6 7 6 7 7 7 6 6 20 FT wind gust.9 10 12 12 12 12 10 10 10 10 10 10 Surface wnd dir.NW NW NW NW NW NW NW NW NW NW NW NW Surface wnd spd.5 6 7 6 6 7 6 7 7 7 6 6 Surface wnd gst.9 10 12 12 12 12 10 10 10 10 10 10 Mix hgt (kft)...1.1 1.9 2.7 3.7 4.7 5.7 6.0 6.4 6.7 6.5 6.3 6.1 Transp wind dir.W NW NW NW NW NW NW NW NW NW NW NW Transp wind spd.6 7 8 8 8 8 8 8 8 8 7 7 LVORI...........5 4 3 3 1 1 1 1 1 1 1 1 ADI.............8 17 27 38 48 52 54 37 38 37 32 31 Haines index....3 3 3 3 3 3 3 3 3 3 3 3 Vrate kt-ft/1K..5 11 19 26 33 40 42 45 47 46 38 37 Ventrate Cat....PR PR PR PR PR PR FR FR FR FR PR PR Ceiling (kft)...14 15 15 13 10 7.0 7.0 6.0 6.0 6.0 6.0 6.0 .TONIGHT... Sky/weather.........Mostly cloudy. Slight chance of rain showers in the evening. Isolated thunderstorms early in the evening. Chance of rain showers after midnight. CWR.................29 percent decreasing to 11 percent until just after midnight, then increasing to 32 percent early in the morning. Min temperature.....Around 53. Max humidity........80 percent. Dewpoint............51 decreasing to 47 early in the morning. Max apparent temp...70. Surface winds (mph).Northwest winds 5 to 6 mph in the evening becoming light, then becoming north 5 to 7 mph around midnight. Wind (20 ft)........North winds 5 to 7 mph in the evening becoming light, then becoming north 5 to 7 mph around midnight. Gusty and erratic winds expected near thunderstorms early in the evening. Mixing height.......400 ft AGL. Transport winds.....North 3 to 8 mph. Smoke dispersal.....Fair (27000 knot-ft) early in the evening decreasing to poor (1500 knot-ft) late in the night. LVORI...............3. ADI.................31 to 35 decreasing to 2 to 5 until just after midnight. Haines Index........3 or very low potential for large plume dominated fire growth. CEILING (KFT).......7.0 increasing to 9.0 early in the evening, then increasing to 10 early decreasing to 9.0 late in the evening decreasing to 8.0 decreasing to 7.0 around midnight increasing to 8.0 decreasing to 7.0 early in the morning decreasing to 6.0. TIME (EDT) 6 PM 8 PM 10 PM MIDNGT 2 AM 4 AM Sky (%).........60 64 72 78 81 81 Weather cov.....S CHC S CHC S CHC S CHC CHANCE CHANCE Weather type....RNSHWR RNSHWR RNSHWR RNSHWR RNSHWR RNSHWR Tstm cov........ISOLTD CWR.............30 10 10 10 30 30 Temp............70 67 63 60 58 56 Dewpoint........52 53 53 52 51 48 RH..............53 61 70 75 77 74 Heat index (F)..70 67 63 60 58 56 20 ft wind......NW 6 NW 6 N 3 N 5 N 7 N 7 20 ft wind gust.9 8 8 9 13 12 Surface wind....NW 6 NW 6 N 3 N 5 N 7 N 7 Surface wnd gst.9 8 8 9 13 12 Mix hgt (ft)....5400 3900 1600 700 1400 900 Transport wind..NW 6 NW 6 N 3 N 5 N 7 N 8 LVORI...........1 3 3 4 4 3 ADI.............35 3 2 3 5 5 Haines index....3 3 3 3 3 3 Vrate kt-ft/1K..27 20 5 3 8 6 Ventrate Cat....POOR POOR POOR POOR POOR POOR Ceiling (kft)...7.0 10 8.0 7.0 8.0 7.0 .THURSDAY... Sky/weather.........Partly sunny. Chance of rain showers through early afternoon, then slight chance of rain showers late in the afternoon. CWR.................33 percent decreasing to 11 percent late in the afternoon. Max temperature.....Around 69. Min humidity........44 percent. Dewpoint............48. Max apparent temp...69. Surface winds (mph).North winds 7 to 8 mph. Wind (20 ft)........North winds 7 to 8 mph. Mixing height.......7900 ft AGL. Transport winds.....North 7 to 8 mph shifting to the northwest around 8 mph late in the afternoon. Smoke dispersal.....Poor (3800 knot-ft) early in the morning increasing to good (55200 knot-ft) in the afternoon. LVORI...............3. ADI.................6 to 15 increasing to 62 to 66. Haines Index........3 or very low potential for large plume dominated fire growth. CEILING (KFT).......6.0 increasing to 9.0. TIME (EDT) 6 AM 9 AM NOON 3 PM Sky (%).........80 75 61 47 Weather cov.....CHANCE CHANCE CHANCE S CHC Weather type....RNSHWR RNSHWR RNSHWR RNSHWR Tstm cov........ CWR.............30 30 30 10 Temp............55 57 63 68 Dewpoint........47 49 47 46 RH..............74 75 56 45 Heat index (F)..55 57 63 68 20 FT wind......N 7G13 N 7G13 N 7G13 N 8G13 Surface wind....N 7G13 N 7G13 N 7G13 N 8G13 Mix hgt (ft)....600 1100 3900 7400 Transport wind..N 8 N 7 N 7 NW 8 LVORI...........3 4 1 1 ADI.............6 9 32 63 Haines index....3 3 3 3 Vrate kt-ft/1K..4 7 23 52 Ventrate Cat....POOR POOR POOR FAIR Ceiling (kft)...6.0 6.0 8.0 8.0 $$ Forecaster...Dooley Requested by...Alex Entrup Type of request...PRESCRIBED .TAG 2415252.0/BOX .DELDT 05/29/24 .FormatterVersion 2.0.0 .EMAIL alex.entrup@mass.gov