Updated 4:19pm — It’s been a long, painful wait for Hawke’s Bay farmers.  It has been very dry and they have been very hopeful for some rain.

So is their long wait just about over, or will the skies only tease?

The first chance for rain will be late today or tonight.  There is a lot of very muggy air in place and all that moisture is being lifted up into the atmosphere.  That is creating an unstable atmosphere and will likely lead to shower development.  A few thunderstorms are also possible. 

However this moisture will be isolated.

Heavy rain is a real possibility through this evening.  In fact, government forecaster MetService says rainfall rates of 25-40 mm/hr are possible.  That would be enough to qualify a storm as severe.  For that reason, MetService has issued a Severe Thunderstorm Watch effective until 9:00pm for Hawke’s Bay.  The watch also covers Taihape, Manawatu and Tararua.

Remember, a “watch” means that conditions are favourable for the development for severe thunderstorms in and close to the watch area.  A “warning” means it is actually happening or is imminent.

That much rain that fast falling over a dry ground is likely to just run off instead of getting soaked in.  So whilst it is good news that rain is on the way, this probably is not quite the farmers are looking for.

However, ex-Tropical Cyclone Evan could help out with something a bit more suitable.

As the low moves west out over the Tasman Sea on Monday, it will help swing the winds around to a more onshore flow for Hawke’s Bay, bringing rain back to the region. 

However computer models are still conflicted – with just 40% confidence of rain by one reliable data provider that WeatherWatch.co.nz heavily relies on.

Highest risk for rain will be Monday and Tuesday – but farmers fears of the rain only being drizzle are possible.  For that reason why advise farmers to monitor forecasts, potential warnings and the latest rain maps at WeatherWatch.co.nz.

Certainly the timing could be a bit better, rather than having it over the Christmas and Boxing Day holidays.  But, for farmers, it could end up being a nice Christmas gift.

As of 4pm Saturday WeatherWatch.co.nz says the chance of rain for Hawkes Bay is around 60% in the north but drops to 40% further south over the next few days.

It remains unclear if Evan will produce enough rain to soak the region – but WeatherWatch.co.nz will continue to monitor and bring updates when anything changes.

40% confidence would usually indicate not a great deal of rain however Evan is creating significant uncertainty, as most tropical lows do all over the world. 

Hompeage image/ File

By Howard Joseph and Philip Duncan, WeatherWatch.co.nz