General May Weather

[spwill]

A thunderstorm risk showing for the west of the North Island later Tuesday and Wednesday. More high pressure from Thursday to keep our weather generally quiet for the time of year.

[NZ Thunderstorm Soc]

Yes, mainly a fine week coming up.
I see MS have issued thunderstorm and snow warnings for the Chatham Islands with this current strong SW flow to the east of us.

[Kobi]

Has been a fine day today, high of 11C, started on 1.5C and will drop to -3C tonight
Next week looking mostly fine, with morning frosts and days with above average temperatures on Friday and Saturday which has happened only twice this month.

[NZ Thunderstorm Soc]

After a frost, a blue dome day eventuated. !!.8C for today with light winds.

[NZ Thunderstorm Soc]

After a good frost, a fine day eventuated with blue skies and some scattered high cloud bits. Not much wind, if so from the NE.
Some high cloud this evening and calm. 11.6C for today.

[JP.]

Christchurch city looks to be on track for one of its coldest May's in the last 10+ years. -3.7 at the airport this morning.

Today marks the 14th below zero morning this month.

[Kobi]

Today marks the 14th below zero morning this month.

And tonight is forecasted to once again drop below 0

[spwill]

15 days this May so far with air frost at Chch airport.

[Bradley]

Even going by the 9am reset time NIWA uses Christchurch Airport is still on track to record the coldest ever May for minimum temperatures with the airport, as of yesterday morning, averaging 1.0C as a minimum, still 0.2C colder then May 1988 which held the previous record and with at least 2 more subzero nights still to come then we can pretty certain it will break that record...

[Kobi]

Even going by the 9am reset time NIWA uses Christchurch Airport is still on track to record the coldest ever May for minimum temperatures with the airport, as of yesterday morning, averaging 1.0C as a minimum, still 0.2C colder then May 1988 which held the previous record and with at least 2 more subzero nights still to come then we can pretty certain it will break that record...

Curious what the coldest may by mean temperature is, and how close this month is to that

[Nev]

Curious what the coldest may by mean temperature is, and how close this month is to that

This month's average Tmean at Chch Aero is currently tracking to be around 7.0C.

Chch Aero coldest May average Tmeans (°C) from records since 1954:
1959 ... 6.4
1992 ... 6.8
2009 ... 6.9
2008 ... 7.1
1984 ... 7.3

[Nev]

15 days this May so far with air frost at Chch airport.

I count 14 screen/air frosts (i.e., below 0.0C) so far at Chch Aero using both midnight and 9am reset times.
Regardless, Chch Aero's previous May record for the most screen/air frost days was 12 in 1988, followed by 11 in 2008.

[Storm Struck]

It might drop to around 0C tonight, but that is closer to 3am as by 6am there's the first cold front coming through.
Initially it wasn't showing anything for Canterbury but last few surface runs have showers in the morning and again from mid afternoon.
The mid afternoon is more coastal and is a trough so will bring a slight risk of thunder but nothing hugely great.
Perhaps some small hail laced in with the showers.

I certainly can't recall such a cold May in my time of observing adverse weather. Yet here go flicking the switch for the first week of winter.

[Andy]

15 days this May so far with air frost at Chch airport.

Yea sitting on 22 air frosts so far in Alexandra. Looks like we skipped May and just had June instead!

[NZ Thunderstorm Soc]

Yes, it does look a bit rough there, David, with a ULT moving across being a culprit enhancing the SW flow.
....anyway, after a frost this morning, another blue dome day eventuated but with some cirrus forms this afternoon, Not much wind and calm this evening. 13.2C for today. Calm and frosty this evening with down to zero at 10pm.

[Kobi]

A nice day today after the frost went away, started on -3.7c, second heaviest frost this year to date, got to a high of about 12C, and back down to 0C for right now at the airport, though 2C at my house

[Nev]

^ Just for the record, Chch Aero recorded a Tmin of -4.0C yesterday and -2.7C on Monday.
Hourly data also suggests that it exceeded -2.0C earlier this morning.

[Bradley]

^ Just for the record, Chch Aero recorded a Tmin of -4.0C yesterday and -2.7C on Monday.
Hourly data also suggests that it exceeded -2.0C earlier this morning.

Definitely on track now after this morning to record the first all-time coldest minimum monthly average temp at the airport in a long, long time

[JP.]

-2.0c at 1am this morning at the airport. Thankfully warming up to 2.1c at 6am as the westerly came in. Definitely on track for a very cold T Min for May

[Kobi]

And another -2c forecasted tonight, also interesting last nights minimum occurred at 1am, guessing the westerly quarter wind change afterwards caused it to slowly warm after that.

[Razor]

Very strong SW wind and sporadic patchy rain now in Lincoln

[NZ Thunderstorm Soc]

Frosty overnight initially but that went off from around dawn as cloud moved in front from the SW with it becoming overcast and dull for much of the day with light SW winds although it slowly cleared up later in the day and evening. 10.3C for today with about 3 spits of drizzle. All rain moved NE out along the coast from the SW therefor missing us here.

[NZ Thunderstorm Soc]

A frosty start but it clouded over during the morning with it coming onto light rain around noon as cloud moved over from the west/SW.
Becoming fine but with high cloud with long lenticular streaks extending from the south to the north along the foothills to the west of here.
Not much wind here today. Today's maximum being 12.3C with 0.7mm of rain.

[Storm Struck]

Down to 3C at the airport and 7C this side of town,shouldn't drop any lower than that as the milder air moves in and cold lingering upper air moves east.
Note Timaru sitting on 18C currently as of 11:24pm, the influence of the warmer Northerly flow.
Next few days temperatures will be interesting then.

Unsure of the Maximum record for June in Canterbury or Christchurch, perhaps Nev can you dig up those wonderful stats .

[Bradley]

0C at the airport, will end up recording 16-17 minimums at 0C or below for the month, remarkable!