tropicbreeze

An extract of RSMC Nadi current 3 day outlook: Issue Time: 0400 UTC Wednesday 21st January 2015 Next Issue: 0400 UTC Thursday 22nd January 2015 Issued By: Tropical Cyclone Centre, RSMC, Nadi Existing Tropical Cyclones: Tropical Cyclone Niko [995hpa] Category 1 was analysed near 14.7S 150.1W north of Tahiti at 210300 UTC. It is moving south-southeast at 10 knots. Position poor.

I think that'd be roughly where the MJO is now. A bit of a boost to the convection.

Highest temperature records are from places below sea level. Marble Bar is about 180 metres above sea level. Imagine what another few hundred metres lower would do to them.

It's been taking a while for that monsoonal grey to dissipate, but finally some sunset colour tonight.

It is an amazing shot, it's shown up on a few threads on Netweather and other weather sites. There's also one taken further along so it's at much more of an angle. And also one with a (that?) storm well away from the eye and showing up as a bright luminescent spot. But it's a long way to go to get a good photo. They were taken by Astronaut Sam Cristoforetti.

Bansi is moving east south east at 15 knots. Central Pressure 956 hPa, wind speed (10 minute) 70 knots, radius of maximum winds 59 kms. It's expected to commence extratropical transition Tuesday.

SEVERE WEATHER BULLETIN NUMBER ELEVEN TROPICAL CYCLONE WARNING: TROPICAL STORM "AMANG" (MEKKHALA) Issued at 11:00 p.m., Saturday, 17 January 2015 Tropical Storm "AMANG" has slightly weakened after it made landfall over Dolores, Eastern Samar and is now moving towards Bicol Region. Location of Centre: (as of 10:00 p.m.) In the vicinity of Catarman, Northern Samar Coordinates: 12.5°N, 124.7°E Strength: Maximum sustained winds of 85 kph near the centre and gustiness of up to 100 kph. Movement: Forecast to move Northwest at 15 kph. Forecast Positions/Outlook: Sunday evening: 125 km Northeast of Infanta, Quezon Monday evening: 115 km East Northeast of Aparri, Cagayan Tuesday evening: 265 km East Northeast of Basco, Batanes

The Philippines is calling this one Amang.

0600UTC 16/01/2015 Bansi had a central pressure 923 hPa, wind speed 115 knots and radius of maximum winds 37 kms. The latest, 1900UTC 16/01/2015, central pressure 935 hPa, wind speed 100 knots and radius of maximum winds 46 kms. Movement to the south east at 11 knots. The eye wall is showing erosion in the northwest.

Bansi is currently moving east south east at 11 knots and could pass within 100 kms of Rodrigues. Central pressure 940 hPa, wind speed (10 minute) 100 knots. radius of maximum winds 39 kms. It should remain in a favourable environment overnight and then come into increasing vertical wind shear with decreasing sea surface temperatures.

Bansi has started to contract, radius of maximum winds is now 48 kms. Wind speed (10 minutes) at 75 knots, central pressure 963 hPa. It's expected to track further east taking it further from Rodrigues. Wind speed is expected to increase to 90 knots in 12 hours, at which stage it will be near to its closest point to Rodrigues, and then weaken from 36 hours on.

The eye wall replacement certainly shook up Bansi. Central pressure now is 960 hPa and wind speed (10 minute) is 80 knots. However, radius of maximum winds has spread out to 65 kms and gales may reach 300 kms. It is expected to regain a peak around 90 knots from 24 to 36 hours. Thereafter weakening should occur as conditions become less favourable.

Bansi is going through a weakening trend due to eye wall replacement and is moving eastwards at 4 knots. Central pressure 938 hPa, wind speed (10 minute) 105 knots, radius of maximum winds 13 kms. Due to a weak steering environment Bansi is expected to move slowly over the next 24 hours and then track southeastwards accelerating over the following few days. Although today and tomorrow conditions are expected to be favourable with good poleward and equatorward outflow from Thursday it's expected to lose the equatorward outflow and then begin to come under increasing vertical wind shear and lower sea surface temperatures.

Recent sat pic.

That looks great, although I prefer seeing it in photos rather than the real thing. Have seen similar effects with salt crystals on salt lakes.

It looks like this low had a slight Fujiwhara interaction with the tropical low to the west. At this stage conditions appear unfavourable for this system to develop into a tropical cyclone. From BRISBANE TROPICAL CYCLONE WARNING CENTRE at 1920 UTC 11/01/2015: REMARKS: Despite a transitory puff of convection near the LLCC during the last few hours, the main deep convection associated with this system continues to be displaced to the north of the low level circulation centre. This is consistent with southerly vertical shear near 20 knots over the system as estimated from AMSU. Dvorak based on a shear pattern with DT of 1.5. MET is 2.0 and PAT is 1.5. Final T 1.5 with CI 2.0. The system is located in an environment characterised by moderate southerly vertical wind shear, which is forecast to only slightly weaken in the next 24 hours, before gradually increasing once more. Intensification to weak TC strength is no longer considered likely, with little dynamic or statistical guidance forecasting this and a brief window of opportunity in a marginal environment at best. Some interaction with the tropical low [06U] to the west likely influenced the track yesterday, leading to a rather rapid SW to WSW motion. This motion appears to have ended during the last 6 hours based on microwave fixes. The upper level trough to the south should become the dominant steering feature today, leading to a change to a SE and eventually ESE track with increasing forward speed. Copyright Commonwealth of Australia

RSMC La Reunion has elevated the system to Tropical Cyclone. It's situated 395 kms to the north of La Reunion and moving south at 11 kph. However later Monday it's expected to turn more to the east avoiding a direct hit. The island has been placed under cyclone pre-alert (or early warning). (Interesting perspective, "The first named tropical storm of 2015...." looks rather odd. We never see it as based on calendar year, this is the 2014/15 cyclone season and we look at it seasonally.)

IDQ20018 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - EASTERN REGION Issued by BRISBANE TROPICAL CYCLONE WARNING CENTRE at: 0049 UTC 11/01/2015 Name: Tropical Low Identifier: 07U Data At: 0000 UTC Latitude: 12.7S Longitude: 159.2E Location Accuracy: within 20 nm [35 km] Movement Towards: south southwest [192 deg] Speed of Movement: 6 knots [11 km/h] Maximum 10-Minute Wind: 30 knots [55 km/h] Maximum 3-Second Wind Gust: 45 knots [85 km/h] Central Pressure: 998 hPa Radius of 34-knot winds NE quadrant: Radius of 34-knot winds SE quadrant: Radius of 34-knot winds SW quadrant: Radius of 34-knot winds NW quadrant: Radius of 48-knot winds NE quadrant: Radius of 48-knot winds SE quadrant: Radius of 48-knot winds SW quadrant: Radius of 48-knot winds NW quadrant: Radius of 64-knot winds: Radius of Maximum Winds: Dvorak Intensity Code: T2.5/2.5/D0.5/24HRS Pressure of outermost isobar: 1002 hPa Radius of outermost closed isobar: 100 nm [185 km] FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure [uTC] : degrees : nm [km]: knots[km/h]: hPa +06: 11/0600: 13.4S 159.2E: 030 [060]: 035 [065]: 994 +12: 11/1200: 14.1S 159.2E: 045 [080]: 035 [065]: 994 +18: 11/1800: 14.8S 159.4E: 055 [105]: 040 [075]: 992 +24: 12/0000: 15.5S 159.7E: 070 [130]: 045 [085]: 989 +36: 12/1200: 17.2S 161.6E: 090 [165]: 050 [095]: 987 +48: 13/0000: 18.1S 164.4E: 110 [200]: 045 [085]: 990 +60: 13/1200: 19.0S 167.9E: 130 [235]: 035 [065]: 997 +72: 14/0000: 21.7S 172.6E: 145 [270]: 030 [055]: 999 992 REMARKS: Overnight the deep convection has continued, with the cloud still separated from the low level centre. Shear pattern used for Dvorak, less than 0.75 deg from LLC. Location good with GMI Microwave Image at 22:36Z. TC genesis still possible through the next 12 to 24 hours. Two channel outflow to NW and SE as the system lies flanked by an upper trough to the south and monsoon return flow to the north. Very high SST [30C]. Shear generally moderate, though forecast to increase in the next 48 hours, which will then lead to more of a baroclinic structure. Copyright Commonwealth of Australia From Nadi RSMC: TROPICAL CYCLONE 3 - DAY OUTLOOK Equator to 25S and 160E to 120W Issue Time: 0400 UTC Saturday 10th January 2015 Next Issue: 0400 UTC Sunday 11th January 2015 Issued By: Tropical Cyclone Centre, RSMC, Nadi Existing Tropical Cyclones: Nil. Likelihood of a tropical cyclone in the region in each of the next three days, TILL 13th January, 2015: A tropical depression located near 11.0S 159.0E is expected to move into Nadi RSMC’s area of responsibility on Sunday 11th January

Looks like it's pretty much over. A lot of people will be thankful for it having come through, from the dry inland to the areas that were being ravaged by bushfires. The last 3 charts at 12 hour intervals.

After 2 weeks of sitting below heavy monsoonal cloud it's finally breaking to give us the first bit of morning colour to the sky for this year.

The low has made a significant move into the interior and is currently 990 hPa. Alice Springs has had about 48mm over the past 24 hours, and Wulungurru (WA/NT border) 74.4mm.

I'm still really only a rank amateur but have picked up lots of bits and pieces over time. One of the early ones I saw was centred about Tennant Creek. There was not a lot of rain from it at the time. But central pressure was right down and the winds were strong. Thought then that if it had have been over the sea it'd probably have been a category 1. Will be interesting to see how this one goes when it's completely inland. It seems to have started out on its cross country trek now. The weather here looks to be changing as a result. I should probably change the title of the thread to something that more appropriately reflects the current situation.

I first heard of this maybe 8 - 10 years ago, where tropical lows or remnant tropical cyclones ramped up over land. The term applied to it then was "landphoon". Basically low latitude desert soils (mainly sands) absorb a lot of heat. As outer rain bands of the systems drop water down onto the soil the heat transfers into the water which evaporates and passes rapidly to the surface. This then creates similar convection to what happens over warm sea waters. There have been studies done on this phenomenon. It doesn't necessarily have to be desert, just sufficiently high temperatures for heat to seep into the ground and then sufficient water to create the convection. In that area around the Kimberley during the months of October, November, December were getting air temperature highs of 40+, ground temperatures were a lot higher. That's a lot of heat transfered into the soil, and that makes for a lot of warm water when the rains come. That's why I suggested a couple of days ago that since this system wasn't going to head out to sea it could become a landphoon.

The MJO is expected to move into the Pacific next week so a lessening of the monsoonal activity is likely. The low near Broome, currently 992hPa, is still stationary. Looks like by Saturday it should start heading south east as a landphoon all the way past Adelaide. Give them a taste of the tropics. ACCESS forecast for 05:00 AEDT on Monday 12 January 2015

G'day Be cause, it is an interesting system, although not destined for tropical cyclone status by all appearances. Not so much in the desert areas at this stage, but looks like it'll soon be heading across the Great Sandy and Gibson Deserts. I'd say they'll appreciate the rain there once it all settles down. IDW28001 Severe Weather Warning for heavy rainfall for people in the Kimberley and North Interior forecast districts Issued at 3:57 pm WST on Wednesday 7 January 2015. For people in parts of WA northeast of a line from Bidyadanga to Giles. This includes people in, near or between the following towns: Broome, Derby and Kuri Bay. Weather Situation A slow moving tropical low lies between Derby and Fitzroy Crossing and is continuing to produce showers and thunderstorms over the Kimberley and northeast parts of the North Interior. This system is expected to remain over land over the western Kimberley then move eastwards on the weekend. There is only a small chance that the system moves over water and develops during Thursday and Friday. Showers and gusty thunderstorms may produce HEAVY RAINFALL that could cause FLASH FLOODING in parts of the warning area. The areas of greatest risk include Derby, Curtin, the Dampier Peninsula and coastal parts to Kuri Bay, then extending towards Broome during Thursday. Flood Advices have also been issued, please refer to http://www.bom.gov.au/wa/warnings/ for full details. As the low deepens during Thursday, strong and squally winds are likely in coastal parts from Broome to the WA/NT border from Thursday afternoon and also in the vicinity of the low. Between 9:00 am and 3:00 pm Wednesday, the following rainfall totals have been recorded: Derby Airport 83 millimetres, Curtin RAAF 72.4 millimetres and Lombadina Airstrip 44.8 millimetres. The overall weather pattern is not unusual for this time of year, but heavy rainfall may occur in some parts of the warning area and cause damage to property and make road conditions hazardous. The Department of Fire and Emergency Services advises that people should: If outside find safe shelter away from trees, power lines, storm water drains and streams. Close your curtains and blinds, and stay inside away from windows. Unplug electrical appliances and do not use land line telephones if there is lightning. If there is flooding, create your own sandbags by using pillow cases filled with sand and place them around doorways to protect your home. Do not drive into water of unknown depth and current. Slow down and turn your headlights on. Be alert and watch for hazards on the road such as fallen power lines and loose debris. If it is raining heavily and you can not see, pull over and park with your hazard lights on until the rain clears. If your home or property has significant damage, like a badly damaged roof or flooding, call the SES on 132 500. The next warning will be issued by 11:00 pm WST Wednesday.