Important flash: cold weather and increased blood pressure!

I'm not very happy with my blood pressure reading today--152/94 is pretty high. I think if I were to go back on hydrochlorothiazide (HZ hereafter) it would decrease to something closer to the normal range. But I want to try and stick it out without the meds at least until my "loading phase" with creatine is finished (in two days).

As far as my blood pressure going up in the cycling off-season, I stumbled across some relevant information yesterday. While researching high blood pressure I found this tidbit:

Question
Blood pressure: Is it affected by cold weather?
Can weather affect blood pressure? I've noticed that my blood pressure is harder to control in the winter.
Answer
from Sheldon G. Sheps, M.D.

Yes, weather can affect blood pressure. Blood pressure generally is higher in the winter and lower in the summer. Why? Cold temperatures cause your blood vessels to narrow (constrict) — which increases blood pressure because more pressure is needed to force blood through a narrower space. Other possible causes of higher blood pressure are weight gain and decreased physical activity in winter.

However, it doesn't take a big cold snap to raise blood pressure. Seasonal blood pressure changes also are found in climates where temperatures may change only a few degrees from summer to winter. In fact, a five-year analysis of the electronic health records of 444,000 adults with high blood pressure in the United States and its territories found that high blood pressure was less controlled in winter than in summer in all cities, from Anchorage, Alaska, to San Juan, Puerto Rico. The implication from such studies is that it may be necessary to adjust high blood pressure medications in some people to continue to control blood pressure in different seasons.

If you have questions about how weather may affect your blood pressure, consult your doctor.

Have I discovered the reason why I am able to pretty much cease taking HZ when the weather's warm? I can't believe warm temperature is solely responsible for the lower blood pressures I see in the summer.

You'd probably have to see me on the bike to appreciate what I'm saying, but I'm telling you I put out major energy--and I'm not talking about over a mere 40 minute span; no, 40 minutes is the minimum. I can go like that for 1, 2, 3--maybe even as long as 5 hours of really intense output.

To make numerical a comparison, I work pretty hard during our strength-training sessions and always have worked up a good sweat by the end--despite having the fan blowing on me. But I've worn my heart rate monitor while doing strength training and my heart rate rarely goes over 140 BPM. By contrast, on the bike it's routine for me to sustain a heart rate in the 150's BPM for a half hour or more, and I'm often taking that up further yet to 160-170 BPM on hills. I'm certain this type of intense and extended aerobic activity has an effect on blood pressure, though I'm willing to concede that temperature could have its effect in addition.