Weather update: temperatures dropped, and precipitation increased

Thursday, August 12, 2021

Jeff Franklin is sharing this week the main observations of the season in terms of temperature and precipitation until August 11. Always good to remember, this information is coming from Kentville Research Development Centre (KRDC), therefore, some differences between locations are possible to be found.

The first table shows the temperature base 5⁰ C and base 10⁰ C from 2018 until 2021 accumulated each year from March 1 until August 11. At the end of each section, it’s possible to see the average of the last 5 and 10 years respectively.

 

Category

2018

2019

2020

2021

5 year average

10 year average

Plant development (Base 5ºC)

1329.5

1192.3

1314.9

1350.0

1286.6

1290.7

Insect development (Base 10º)

817.2

673.8

812.8

792.7

764.2

760.7

Figure 1. Degree day accumulations as of August 11, 2021.  All data are taken from the Kentville weather station, based on a start date of March 1, and calculated using the single sine method.

Currently, it’s possible to see in 2021 a slightly decrease in the accumulation of heat units, being 2018 and 2020 higher with 817.2 and 812.8 respectively. Jeff reports us that July has the mean temperature for that month of 1.4 °C lower than the 10-year average (19.1 °C compared to 20.5 °C). Even though this diminishment of the temperatures, 2021 still presents a higher accumulation with 792.7 compared with the 5- and 10-year average with 764.2 and 760.7 respectively.

In the following column graph, it’s possible to see the values from 2004 until 2021 and at the end you can see the average of the last 5 and 10 years respectively.

Figure 2. Degree day accumulations as of August 11, 2021 base 10⁰ C.  All data are taken from the Kentville weather station, based on a start date of March 1, and calculated using the single sine method.

This graph confirms our previous comments about the lower accumulation through July and the season 2018 and 2020 have a higher accumulation. Like the previous weather update, it’s quite interesting to see how 2006 had even a higher accumulation until this date, similarly as in the case of 2012 and 2013.

 

In relation to precipitations, Jeff informs us with precipitation totals in July were approximately twice the 10-year average. Moreover, already in the first 11 days of August, we have received half of the expected precipitation for this month. Keep in mind, 50mm of precipitation in July were received in a 45-minute period on the 21st with thunderstorms. This was a localized event and it did not impact the entire Annapolis Valley.

 

2021

 

Precipitation (mm)

10 Year Average

2011 to 2020

Precipitation (mm)

June

35.9

104.3

July

164.4

84.7

August

         48.3***

90.2

                                          ***Data for the first 11 days of August

Figure 3. Precipitation in June, July and first 11 days of August in 2021 and the average of the last 10 year (2011-2020).

In the following photos it’s possible to observe grapevines at different stages.

Figure 4. On the left Castel and on the right Lucie Kuhlmann


Figure 5. On the left Seyval and on the right L’Acadie blanc


Figure 6. On the left Riesling and on the right Chardonnay